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 #define VP_INVAL U32_MAX
13
14 struct ms_hyperv_info {
15 u32 features;
16 u32 misc_features;
17 u32 hints;
18 u32 nested_features;
19 u32 max_vp_index;
20 u32 max_lp_index;
21 };
22
23 extern struct ms_hyperv_info ms_hyperv;
24
25 /*
26 * Generate the guest ID.
27 */
28
generate_guest_id(__u64 d_info1,__u64 kernel_version,__u64 d_info2)29 static inline __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version,
30 __u64 d_info2)
31 {
32 __u64 guest_id = 0;
33
34 guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48);
35 guest_id |= (d_info1 << 48);
36 guest_id |= (kernel_version << 16);
37 guest_id |= d_info2;
38
39 return guest_id;
40 }
41
42
43 /* Free the message slot and signal end-of-message if required */
vmbus_signal_eom(struct hv_message * msg,u32 old_msg_type)44 static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type)
45 {
46 /*
47 * On crash we're reading some other CPU's message page and we need
48 * to be careful: this other CPU may already had cleared the header
49 * and the host may already had delivered some other message there.
50 * In case we blindly write msg->header.message_type we're going
51 * to lose it. We can still lose a message of the same type but
52 * we count on the fact that there can only be one
53 * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages
54 * on crash.
55 */
56 if (cmpxchg(&msg->header.message_type, old_msg_type,
57 HVMSG_NONE) != old_msg_type)
58 return;
59
60 /*
61 * Make sure the write to MessageType (ie set to
62 * HVMSG_NONE) happens before we read the
63 * MessagePending and EOMing. Otherwise, the EOMing
64 * will not deliver any more messages since there is
65 * no empty slot
66 */
67 mb();
68
69 if (msg->header.message_flags.msg_pending) {
70 /*
71 * This will cause message queue rescan to
72 * possibly deliver another msg from the
73 * hypervisor
74 */
75 wrmsrl(HV_X64_MSR_EOM, 0);
76 }
77 }
78
79 #define hv_init_timer(timer, tick) \
80 wrmsrl(HV_X64_MSR_STIMER0_COUNT + (2*timer), tick)
81 #define hv_init_timer_config(timer, val) \
82 wrmsrl(HV_X64_MSR_STIMER0_CONFIG + (2*timer), val)
83
84 #define hv_get_simp(val) rdmsrl(HV_X64_MSR_SIMP, val)
85 #define hv_set_simp(val) wrmsrl(HV_X64_MSR_SIMP, val)
86
87 #define hv_get_siefp(val) rdmsrl(HV_X64_MSR_SIEFP, val)
88 #define hv_set_siefp(val) wrmsrl(HV_X64_MSR_SIEFP, val)
89
90 #define hv_get_synic_state(val) rdmsrl(HV_X64_MSR_SCONTROL, val)
91 #define hv_set_synic_state(val) wrmsrl(HV_X64_MSR_SCONTROL, val)
92
93 #define hv_get_vp_index(index) rdmsrl(HV_X64_MSR_VP_INDEX, index)
94
95 #define hv_get_synint_state(int_num, val) \
96 rdmsrl(HV_X64_MSR_SINT0 + int_num, val)
97 #define hv_set_synint_state(int_num, val) \
98 wrmsrl(HV_X64_MSR_SINT0 + int_num, val)
99
100 #define hv_get_crash_ctl(val) \
101 rdmsrl(HV_X64_MSR_CRASH_CTL, val)
102
103 void hyperv_callback_vector(void);
104 void hyperv_reenlightenment_vector(void);
105 #ifdef CONFIG_TRACING
106 #define trace_hyperv_callback_vector hyperv_callback_vector
107 #endif
108 void hyperv_vector_handler(struct pt_regs *regs);
109 void hv_setup_vmbus_irq(void (*handler)(void));
110 void hv_remove_vmbus_irq(void);
111
112 void hv_setup_kexec_handler(void (*handler)(void));
113 void hv_remove_kexec_handler(void);
114 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs));
115 void hv_remove_crash_handler(void);
116
117 /*
118 * Routines for stimer0 Direct Mode handling.
119 * On x86/x64, there are no percpu actions to take.
120 */
121 void hv_stimer0_vector_handler(struct pt_regs *regs);
122 void hv_stimer0_callback_vector(void);
123 int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void));
124 void hv_remove_stimer0_irq(int irq);
125
hv_enable_stimer0_percpu_irq(int irq)126 static inline void hv_enable_stimer0_percpu_irq(int irq) {}
hv_disable_stimer0_percpu_irq(int irq)127 static inline void hv_disable_stimer0_percpu_irq(int irq) {}
128
129
130 #if IS_ENABLED(CONFIG_HYPERV)
131 extern struct clocksource *hyperv_cs;
132 extern void *hv_hypercall_pg;
133 extern void __percpu **hyperv_pcpu_input_arg;
134
hv_do_hypercall(u64 control,void * input,void * output)135 static inline u64 hv_do_hypercall(u64 control, void *input, void *output)
136 {
137 u64 input_address = input ? virt_to_phys(input) : 0;
138 u64 output_address = output ? virt_to_phys(output) : 0;
139 u64 hv_status;
140
141 #ifdef CONFIG_X86_64
142 if (!hv_hypercall_pg)
143 return U64_MAX;
144
145 __asm__ __volatile__("mov %4, %%r8\n"
146 CALL_NOSPEC
147 : "=a" (hv_status), ASM_CALL_CONSTRAINT,
148 "+c" (control), "+d" (input_address)
149 : "r" (output_address),
150 THUNK_TARGET(hv_hypercall_pg)
151 : "cc", "memory", "r8", "r9", "r10", "r11");
152 #else
153 u32 input_address_hi = upper_32_bits(input_address);
154 u32 input_address_lo = lower_32_bits(input_address);
155 u32 output_address_hi = upper_32_bits(output_address);
156 u32 output_address_lo = lower_32_bits(output_address);
157
158 if (!hv_hypercall_pg)
159 return U64_MAX;
160
161 __asm__ __volatile__(CALL_NOSPEC
162 : "=A" (hv_status),
163 "+c" (input_address_lo), ASM_CALL_CONSTRAINT
164 : "A" (control),
165 "b" (input_address_hi),
166 "D"(output_address_hi), "S"(output_address_lo),
167 THUNK_TARGET(hv_hypercall_pg)
168 : "cc", "memory");
169 #endif /* !x86_64 */
170 return hv_status;
171 }
172
173 /* Fast hypercall with 8 bytes of input and no output */
hv_do_fast_hypercall8(u16 code,u64 input1)174 static inline u64 hv_do_fast_hypercall8(u16 code, u64 input1)
175 {
176 u64 hv_status, control = (u64)code | HV_HYPERCALL_FAST_BIT;
177
178 #ifdef CONFIG_X86_64
179 {
180 __asm__ __volatile__(CALL_NOSPEC
181 : "=a" (hv_status), ASM_CALL_CONSTRAINT,
182 "+c" (control), "+d" (input1)
183 : THUNK_TARGET(hv_hypercall_pg)
184 : "cc", "r8", "r9", "r10", "r11");
185 }
186 #else
187 {
188 u32 input1_hi = upper_32_bits(input1);
189 u32 input1_lo = lower_32_bits(input1);
190
191 __asm__ __volatile__ (CALL_NOSPEC
192 : "=A"(hv_status),
193 "+c"(input1_lo),
194 ASM_CALL_CONSTRAINT
195 : "A" (control),
196 "b" (input1_hi),
197 THUNK_TARGET(hv_hypercall_pg)
198 : "cc", "edi", "esi");
199 }
200 #endif
201 return hv_status;
202 }
203
204 /* Fast hypercall with 16 bytes of input */
hv_do_fast_hypercall16(u16 code,u64 input1,u64 input2)205 static inline u64 hv_do_fast_hypercall16(u16 code, u64 input1, u64 input2)
206 {
207 u64 hv_status, control = (u64)code | HV_HYPERCALL_FAST_BIT;
208
209 #ifdef CONFIG_X86_64
210 {
211 __asm__ __volatile__("mov %4, %%r8\n"
212 CALL_NOSPEC
213 : "=a" (hv_status), ASM_CALL_CONSTRAINT,
214 "+c" (control), "+d" (input1)
215 : "r" (input2),
216 THUNK_TARGET(hv_hypercall_pg)
217 : "cc", "r8", "r9", "r10", "r11");
218 }
219 #else
220 {
221 u32 input1_hi = upper_32_bits(input1);
222 u32 input1_lo = lower_32_bits(input1);
223 u32 input2_hi = upper_32_bits(input2);
224 u32 input2_lo = lower_32_bits(input2);
225
226 __asm__ __volatile__ (CALL_NOSPEC
227 : "=A"(hv_status),
228 "+c"(input1_lo), ASM_CALL_CONSTRAINT
229 : "A" (control), "b" (input1_hi),
230 "D"(input2_hi), "S"(input2_lo),
231 THUNK_TARGET(hv_hypercall_pg)
232 : "cc");
233 }
234 #endif
235 return hv_status;
236 }
237
238 /*
239 * Rep hypercalls. Callers of this functions are supposed to ensure that
240 * rep_count and varhead_size comply with Hyper-V hypercall definition.
241 */
hv_do_rep_hypercall(u16 code,u16 rep_count,u16 varhead_size,void * input,void * output)242 static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size,
243 void *input, void *output)
244 {
245 u64 control = code;
246 u64 status;
247 u16 rep_comp;
248
249 control |= (u64)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET;
250 control |= (u64)rep_count << HV_HYPERCALL_REP_COMP_OFFSET;
251
252 do {
253 status = hv_do_hypercall(control, input, output);
254 if ((status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS)
255 return status;
256
257 /* Bits 32-43 of status have 'Reps completed' data. */
258 rep_comp = (status & HV_HYPERCALL_REP_COMP_MASK) >>
259 HV_HYPERCALL_REP_COMP_OFFSET;
260
261 control &= ~HV_HYPERCALL_REP_START_MASK;
262 control |= (u64)rep_comp << HV_HYPERCALL_REP_START_OFFSET;
263
264 touch_nmi_watchdog();
265 } while (rep_comp < rep_count);
266
267 return status;
268 }
269
270 /*
271 * Hypervisor's notion of virtual processor ID is different from
272 * Linux' notion of CPU ID. This information can only be retrieved
273 * in the context of the calling CPU. Setup a map for easy access
274 * to this information.
275 */
276 extern u32 *hv_vp_index;
277 extern u32 hv_max_vp_index;
278 extern struct hv_vp_assist_page **hv_vp_assist_page;
279
hv_get_vp_assist_page(unsigned int cpu)280 static inline struct hv_vp_assist_page *hv_get_vp_assist_page(unsigned int cpu)
281 {
282 if (!hv_vp_assist_page)
283 return NULL;
284
285 return hv_vp_assist_page[cpu];
286 }
287
288 /**
289 * hv_cpu_number_to_vp_number() - Map CPU to VP.
290 * @cpu_number: CPU number in Linux terms
291 *
292 * This function returns the mapping between the Linux processor
293 * number and the hypervisor's virtual processor number, useful
294 * in making hypercalls and such that talk about specific
295 * processors.
296 *
297 * Return: Virtual processor number in Hyper-V terms
298 */
hv_cpu_number_to_vp_number(int cpu_number)299 static inline int hv_cpu_number_to_vp_number(int cpu_number)
300 {
301 return hv_vp_index[cpu_number];
302 }
303
cpumask_to_vpset(struct hv_vpset * vpset,const struct cpumask * cpus)304 static inline int cpumask_to_vpset(struct hv_vpset *vpset,
305 const struct cpumask *cpus)
306 {
307 int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
308
309 /* valid_bank_mask can represent up to 64 banks */
310 if (hv_max_vp_index / 64 >= 64)
311 return 0;
312
313 /*
314 * Clear all banks up to the maximum possible bank as hv_tlb_flush_ex
315 * structs are not cleared between calls, we risk flushing unneeded
316 * vCPUs otherwise.
317 */
318 for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++)
319 vpset->bank_contents[vcpu_bank] = 0;
320
321 /*
322 * Some banks may end up being empty but this is acceptable.
323 */
324 for_each_cpu(cpu, cpus) {
325 vcpu = hv_cpu_number_to_vp_number(cpu);
326 if (vcpu == VP_INVAL)
327 return -1;
328 vcpu_bank = vcpu / 64;
329 vcpu_offset = vcpu % 64;
330 __set_bit(vcpu_offset, (unsigned long *)
331 &vpset->bank_contents[vcpu_bank]);
332 if (vcpu_bank >= nr_bank)
333 nr_bank = vcpu_bank + 1;
334 }
335 vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
336 return nr_bank;
337 }
338
339 void __init hyperv_init(void);
340 void hyperv_setup_mmu_ops(void);
341 void hyperv_report_panic(struct pt_regs *regs, long err);
342 void hyperv_report_panic_msg(phys_addr_t pa, size_t size);
343 bool hv_is_hyperv_initialized(void);
344 void hyperv_cleanup(void);
345
346 void hyperv_reenlightenment_intr(struct pt_regs *regs);
347 void set_hv_tscchange_cb(void (*cb)(void));
348 void clear_hv_tscchange_cb(void);
349 void hyperv_stop_tsc_emulation(void);
350 int hyperv_flush_guest_mapping(u64 as);
351
352 #ifdef CONFIG_X86_64
353 void hv_apic_init(void);
354 #else
hv_apic_init(void)355 static inline void hv_apic_init(void) {}
356 #endif
357
358 #else /* CONFIG_HYPERV */
hyperv_init(void)359 static inline void hyperv_init(void) {}
hv_is_hyperv_initialized(void)360 static inline bool hv_is_hyperv_initialized(void) { return false; }
hyperv_cleanup(void)361 static inline void hyperv_cleanup(void) {}
hyperv_setup_mmu_ops(void)362 static inline void hyperv_setup_mmu_ops(void) {}
set_hv_tscchange_cb(void (* cb)(void))363 static inline void set_hv_tscchange_cb(void (*cb)(void)) {}
clear_hv_tscchange_cb(void)364 static inline void clear_hv_tscchange_cb(void) {}
hyperv_stop_tsc_emulation(void)365 static inline void hyperv_stop_tsc_emulation(void) {};
hv_get_vp_assist_page(unsigned int cpu)366 static inline struct hv_vp_assist_page *hv_get_vp_assist_page(unsigned int cpu)
367 {
368 return NULL;
369 }
hyperv_flush_guest_mapping(u64 as)370 static inline int hyperv_flush_guest_mapping(u64 as) { return -1; }
371 #endif /* CONFIG_HYPERV */
372
373 #ifdef CONFIG_HYPERV_TSCPAGE
374 struct ms_hyperv_tsc_page *hv_get_tsc_page(void);
hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page * tsc_pg,u64 * cur_tsc)375 static inline u64 hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page *tsc_pg,
376 u64 *cur_tsc)
377 {
378 u64 scale, offset;
379 u32 sequence;
380
381 /*
382 * The protocol for reading Hyper-V TSC page is specified in Hypervisor
383 * Top-Level Functional Specification ver. 3.0 and above. To get the
384 * reference time we must do the following:
385 * - READ ReferenceTscSequence
386 * A special '0' value indicates the time source is unreliable and we
387 * need to use something else. The currently published specification
388 * versions (up to 4.0b) contain a mistake and wrongly claim '-1'
389 * instead of '0' as the special value, see commit c35b82ef0294.
390 * - ReferenceTime =
391 * ((RDTSC() * ReferenceTscScale) >> 64) + ReferenceTscOffset
392 * - READ ReferenceTscSequence again. In case its value has changed
393 * since our first reading we need to discard ReferenceTime and repeat
394 * the whole sequence as the hypervisor was updating the page in
395 * between.
396 */
397 do {
398 sequence = READ_ONCE(tsc_pg->tsc_sequence);
399 if (!sequence)
400 return U64_MAX;
401 /*
402 * Make sure we read sequence before we read other values from
403 * TSC page.
404 */
405 smp_rmb();
406
407 scale = READ_ONCE(tsc_pg->tsc_scale);
408 offset = READ_ONCE(tsc_pg->tsc_offset);
409 *cur_tsc = rdtsc_ordered();
410
411 /*
412 * Make sure we read sequence after we read all other values
413 * from TSC page.
414 */
415 smp_rmb();
416
417 } while (READ_ONCE(tsc_pg->tsc_sequence) != sequence);
418
419 return mul_u64_u64_shr(*cur_tsc, scale, 64) + offset;
420 }
421
hv_read_tsc_page(const struct ms_hyperv_tsc_page * tsc_pg)422 static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg)
423 {
424 u64 cur_tsc;
425
426 return hv_read_tsc_page_tsc(tsc_pg, &cur_tsc);
427 }
428
429 #else
hv_get_tsc_page(void)430 static inline struct ms_hyperv_tsc_page *hv_get_tsc_page(void)
431 {
432 return NULL;
433 }
434
hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page * tsc_pg,u64 * cur_tsc)435 static inline u64 hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page *tsc_pg,
436 u64 *cur_tsc)
437 {
438 BUG();
439 return U64_MAX;
440 }
441 #endif
442 #endif
443
