xref: /openbmc/linux/arch/x86/include/asm/paravirt.h (revision d3402925)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_PARAVIRT_H
3 #define _ASM_X86_PARAVIRT_H
4 /* Various instructions on x86 need to be replaced for
5  * para-virtualization: those hooks are defined here. */
6 
7 #include <asm/paravirt_types.h>
8 
9 #ifdef CONFIG_PARAVIRT
10 #include <asm/pgtable_types.h>
11 #include <asm/asm.h>
12 #include <asm/nospec-branch.h>
13 
14 #ifndef __ASSEMBLY__
15 #include <linux/bug.h>
16 #include <linux/types.h>
17 #include <linux/cpumask.h>
18 #include <linux/static_call_types.h>
19 #include <asm/frame.h>
20 
21 u64 dummy_steal_clock(int cpu);
22 u64 dummy_sched_clock(void);
23 
24 DECLARE_STATIC_CALL(pv_steal_clock, dummy_steal_clock);
25 DECLARE_STATIC_CALL(pv_sched_clock, dummy_sched_clock);
26 
27 void paravirt_set_sched_clock(u64 (*func)(void));
28 
29 static __always_inline u64 paravirt_sched_clock(void)
30 {
31 	return static_call(pv_sched_clock)();
32 }
33 
34 struct static_key;
35 extern struct static_key paravirt_steal_enabled;
36 extern struct static_key paravirt_steal_rq_enabled;
37 
38 __visible void __native_queued_spin_unlock(struct qspinlock *lock);
39 bool pv_is_native_spin_unlock(void);
40 __visible bool __native_vcpu_is_preempted(long cpu);
41 bool pv_is_native_vcpu_is_preempted(void);
42 
43 static inline u64 paravirt_steal_clock(int cpu)
44 {
45 	return static_call(pv_steal_clock)(cpu);
46 }
47 
48 #ifdef CONFIG_PARAVIRT_SPINLOCKS
49 void __init paravirt_set_cap(void);
50 #endif
51 
52 /* The paravirtualized I/O functions */
53 static inline void slow_down_io(void)
54 {
55 	PVOP_VCALL0(cpu.io_delay);
56 #ifdef REALLY_SLOW_IO
57 	PVOP_VCALL0(cpu.io_delay);
58 	PVOP_VCALL0(cpu.io_delay);
59 	PVOP_VCALL0(cpu.io_delay);
60 #endif
61 }
62 
63 void native_flush_tlb_local(void);
64 void native_flush_tlb_global(void);
65 void native_flush_tlb_one_user(unsigned long addr);
66 void native_flush_tlb_multi(const struct cpumask *cpumask,
67 			     const struct flush_tlb_info *info);
68 
69 static inline void __flush_tlb_local(void)
70 {
71 	PVOP_VCALL0(mmu.flush_tlb_user);
72 }
73 
74 static inline void __flush_tlb_global(void)
75 {
76 	PVOP_VCALL0(mmu.flush_tlb_kernel);
77 }
78 
79 static inline void __flush_tlb_one_user(unsigned long addr)
80 {
81 	PVOP_VCALL1(mmu.flush_tlb_one_user, addr);
82 }
83 
84 static inline void __flush_tlb_multi(const struct cpumask *cpumask,
85 				      const struct flush_tlb_info *info)
86 {
87 	PVOP_VCALL2(mmu.flush_tlb_multi, cpumask, info);
88 }
89 
90 static inline void paravirt_tlb_remove_table(struct mmu_gather *tlb, void *table)
91 {
92 	PVOP_VCALL2(mmu.tlb_remove_table, tlb, table);
93 }
94 
95 static inline void paravirt_arch_exit_mmap(struct mm_struct *mm)
96 {
97 	PVOP_VCALL1(mmu.exit_mmap, mm);
98 }
99 
100 static inline void notify_page_enc_status_changed(unsigned long pfn,
101 						  int npages, bool enc)
102 {
103 	PVOP_VCALL3(mmu.notify_page_enc_status_changed, pfn, npages, enc);
104 }
105 
106 #ifdef CONFIG_PARAVIRT_XXL
107 static inline void load_sp0(unsigned long sp0)
108 {
109 	PVOP_VCALL1(cpu.load_sp0, sp0);
110 }
111 
112 /* The paravirtualized CPUID instruction. */
113 static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
114 			   unsigned int *ecx, unsigned int *edx)
115 {
116 	PVOP_VCALL4(cpu.cpuid, eax, ebx, ecx, edx);
117 }
118 
119 /*
120  * These special macros can be used to get or set a debugging register
121  */
122 static __always_inline unsigned long paravirt_get_debugreg(int reg)
123 {
124 	return PVOP_CALL1(unsigned long, cpu.get_debugreg, reg);
125 }
126 #define get_debugreg(var, reg) var = paravirt_get_debugreg(reg)
127 static __always_inline void set_debugreg(unsigned long val, int reg)
128 {
129 	PVOP_VCALL2(cpu.set_debugreg, reg, val);
130 }
131 
132 static inline unsigned long read_cr0(void)
133 {
134 	return PVOP_CALL0(unsigned long, cpu.read_cr0);
135 }
136 
137 static inline void write_cr0(unsigned long x)
138 {
139 	PVOP_VCALL1(cpu.write_cr0, x);
140 }
141 
142 static __always_inline unsigned long read_cr2(void)
143 {
144 	return PVOP_ALT_CALLEE0(unsigned long, mmu.read_cr2,
145 				"mov %%cr2, %%rax;",
146 				ALT_NOT(X86_FEATURE_XENPV));
147 }
148 
149 static __always_inline void write_cr2(unsigned long x)
150 {
151 	PVOP_VCALL1(mmu.write_cr2, x);
152 }
153 
154 static inline unsigned long __read_cr3(void)
155 {
156 	return PVOP_ALT_CALL0(unsigned long, mmu.read_cr3,
157 			      "mov %%cr3, %%rax;", ALT_NOT(X86_FEATURE_XENPV));
158 }
159 
160 static inline void write_cr3(unsigned long x)
161 {
162 	PVOP_ALT_VCALL1(mmu.write_cr3, x,
163 			"mov %%rdi, %%cr3", ALT_NOT(X86_FEATURE_XENPV));
164 }
165 
166 static inline void __write_cr4(unsigned long x)
167 {
168 	PVOP_VCALL1(cpu.write_cr4, x);
169 }
170 
171 static __always_inline void arch_safe_halt(void)
172 {
173 	PVOP_VCALL0(irq.safe_halt);
174 }
175 
176 static inline void halt(void)
177 {
178 	PVOP_VCALL0(irq.halt);
179 }
180 
181 extern noinstr void pv_native_wbinvd(void);
182 
183 static __always_inline void wbinvd(void)
184 {
185 	PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", ALT_NOT(X86_FEATURE_XENPV));
186 }
187 
188 static inline u64 paravirt_read_msr(unsigned msr)
189 {
190 	return PVOP_CALL1(u64, cpu.read_msr, msr);
191 }
192 
193 static inline void paravirt_write_msr(unsigned msr,
194 				      unsigned low, unsigned high)
195 {
196 	PVOP_VCALL3(cpu.write_msr, msr, low, high);
197 }
198 
199 static inline u64 paravirt_read_msr_safe(unsigned msr, int *err)
200 {
201 	return PVOP_CALL2(u64, cpu.read_msr_safe, msr, err);
202 }
203 
204 static inline int paravirt_write_msr_safe(unsigned msr,
205 					  unsigned low, unsigned high)
206 {
207 	return PVOP_CALL3(int, cpu.write_msr_safe, msr, low, high);
208 }
209 
210 #define rdmsr(msr, val1, val2)			\
211 do {						\
212 	u64 _l = paravirt_read_msr(msr);	\
213 	val1 = (u32)_l;				\
214 	val2 = _l >> 32;			\
215 } while (0)
216 
217 #define wrmsr(msr, val1, val2)			\
218 do {						\
219 	paravirt_write_msr(msr, val1, val2);	\
220 } while (0)
221 
222 #define rdmsrl(msr, val)			\
223 do {						\
224 	val = paravirt_read_msr(msr);		\
225 } while (0)
226 
227 static inline void wrmsrl(unsigned msr, u64 val)
228 {
229 	wrmsr(msr, (u32)val, (u32)(val>>32));
230 }
231 
232 #define wrmsr_safe(msr, a, b)	paravirt_write_msr_safe(msr, a, b)
233 
234 /* rdmsr with exception handling */
235 #define rdmsr_safe(msr, a, b)				\
236 ({							\
237 	int _err;					\
238 	u64 _l = paravirt_read_msr_safe(msr, &_err);	\
239 	(*a) = (u32)_l;					\
240 	(*b) = _l >> 32;				\
241 	_err;						\
242 })
243 
244 static inline int rdmsrl_safe(unsigned msr, unsigned long long *p)
245 {
246 	int err;
247 
248 	*p = paravirt_read_msr_safe(msr, &err);
249 	return err;
250 }
251 
252 static inline unsigned long long paravirt_read_pmc(int counter)
253 {
254 	return PVOP_CALL1(u64, cpu.read_pmc, counter);
255 }
256 
257 #define rdpmc(counter, low, high)		\
258 do {						\
259 	u64 _l = paravirt_read_pmc(counter);	\
260 	low = (u32)_l;				\
261 	high = _l >> 32;			\
262 } while (0)
263 
264 #define rdpmcl(counter, val) ((val) = paravirt_read_pmc(counter))
265 
266 static inline void paravirt_alloc_ldt(struct desc_struct *ldt, unsigned entries)
267 {
268 	PVOP_VCALL2(cpu.alloc_ldt, ldt, entries);
269 }
270 
271 static inline void paravirt_free_ldt(struct desc_struct *ldt, unsigned entries)
272 {
273 	PVOP_VCALL2(cpu.free_ldt, ldt, entries);
274 }
275 
276 static inline void load_TR_desc(void)
277 {
278 	PVOP_VCALL0(cpu.load_tr_desc);
279 }
280 static inline void load_gdt(const struct desc_ptr *dtr)
281 {
282 	PVOP_VCALL1(cpu.load_gdt, dtr);
283 }
284 static inline void load_idt(const struct desc_ptr *dtr)
285 {
286 	PVOP_VCALL1(cpu.load_idt, dtr);
287 }
288 static inline void set_ldt(const void *addr, unsigned entries)
289 {
290 	PVOP_VCALL2(cpu.set_ldt, addr, entries);
291 }
292 static inline unsigned long paravirt_store_tr(void)
293 {
294 	return PVOP_CALL0(unsigned long, cpu.store_tr);
295 }
296 
297 #define store_tr(tr)	((tr) = paravirt_store_tr())
298 static inline void load_TLS(struct thread_struct *t, unsigned cpu)
299 {
300 	PVOP_VCALL2(cpu.load_tls, t, cpu);
301 }
302 
303 static inline void load_gs_index(unsigned int gs)
304 {
305 	PVOP_VCALL1(cpu.load_gs_index, gs);
306 }
307 
308 static inline void write_ldt_entry(struct desc_struct *dt, int entry,
309 				   const void *desc)
310 {
311 	PVOP_VCALL3(cpu.write_ldt_entry, dt, entry, desc);
312 }
313 
314 static inline void write_gdt_entry(struct desc_struct *dt, int entry,
315 				   void *desc, int type)
316 {
317 	PVOP_VCALL4(cpu.write_gdt_entry, dt, entry, desc, type);
318 }
319 
320 static inline void write_idt_entry(gate_desc *dt, int entry, const gate_desc *g)
321 {
322 	PVOP_VCALL3(cpu.write_idt_entry, dt, entry, g);
323 }
324 
325 #ifdef CONFIG_X86_IOPL_IOPERM
326 static inline void tss_invalidate_io_bitmap(void)
327 {
328 	PVOP_VCALL0(cpu.invalidate_io_bitmap);
329 }
330 
331 static inline void tss_update_io_bitmap(void)
332 {
333 	PVOP_VCALL0(cpu.update_io_bitmap);
334 }
335 #endif
336 
337 static inline void paravirt_activate_mm(struct mm_struct *prev,
338 					struct mm_struct *next)
339 {
340 	PVOP_VCALL2(mmu.activate_mm, prev, next);
341 }
342 
343 static inline void paravirt_arch_dup_mmap(struct mm_struct *oldmm,
344 					  struct mm_struct *mm)
345 {
346 	PVOP_VCALL2(mmu.dup_mmap, oldmm, mm);
347 }
348 
349 static inline int paravirt_pgd_alloc(struct mm_struct *mm)
350 {
351 	return PVOP_CALL1(int, mmu.pgd_alloc, mm);
352 }
353 
354 static inline void paravirt_pgd_free(struct mm_struct *mm, pgd_t *pgd)
355 {
356 	PVOP_VCALL2(mmu.pgd_free, mm, pgd);
357 }
358 
359 static inline void paravirt_alloc_pte(struct mm_struct *mm, unsigned long pfn)
360 {
361 	PVOP_VCALL2(mmu.alloc_pte, mm, pfn);
362 }
363 static inline void paravirt_release_pte(unsigned long pfn)
364 {
365 	PVOP_VCALL1(mmu.release_pte, pfn);
366 }
367 
368 static inline void paravirt_alloc_pmd(struct mm_struct *mm, unsigned long pfn)
369 {
370 	PVOP_VCALL2(mmu.alloc_pmd, mm, pfn);
371 }
372 
373 static inline void paravirt_release_pmd(unsigned long pfn)
374 {
375 	PVOP_VCALL1(mmu.release_pmd, pfn);
376 }
377 
378 static inline void paravirt_alloc_pud(struct mm_struct *mm, unsigned long pfn)
379 {
380 	PVOP_VCALL2(mmu.alloc_pud, mm, pfn);
381 }
382 static inline void paravirt_release_pud(unsigned long pfn)
383 {
384 	PVOP_VCALL1(mmu.release_pud, pfn);
385 }
386 
387 static inline void paravirt_alloc_p4d(struct mm_struct *mm, unsigned long pfn)
388 {
389 	PVOP_VCALL2(mmu.alloc_p4d, mm, pfn);
390 }
391 
392 static inline void paravirt_release_p4d(unsigned long pfn)
393 {
394 	PVOP_VCALL1(mmu.release_p4d, pfn);
395 }
396 
397 static inline pte_t __pte(pteval_t val)
398 {
399 	return (pte_t) { PVOP_ALT_CALLEE1(pteval_t, mmu.make_pte, val,
400 					  "mov %%rdi, %%rax",
401 					  ALT_NOT(X86_FEATURE_XENPV)) };
402 }
403 
404 static inline pteval_t pte_val(pte_t pte)
405 {
406 	return PVOP_ALT_CALLEE1(pteval_t, mmu.pte_val, pte.pte,
407 				"mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
408 }
409 
410 static inline pgd_t __pgd(pgdval_t val)
411 {
412 	return (pgd_t) { PVOP_ALT_CALLEE1(pgdval_t, mmu.make_pgd, val,
413 					  "mov %%rdi, %%rax",
414 					  ALT_NOT(X86_FEATURE_XENPV)) };
415 }
416 
417 static inline pgdval_t pgd_val(pgd_t pgd)
418 {
419 	return PVOP_ALT_CALLEE1(pgdval_t, mmu.pgd_val, pgd.pgd,
420 				"mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
421 }
422 
423 #define  __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
424 static inline pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr,
425 					   pte_t *ptep)
426 {
427 	pteval_t ret;
428 
429 	ret = PVOP_CALL3(pteval_t, mmu.ptep_modify_prot_start, vma, addr, ptep);
430 
431 	return (pte_t) { .pte = ret };
432 }
433 
434 static inline void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
435 					   pte_t *ptep, pte_t old_pte, pte_t pte)
436 {
437 
438 	PVOP_VCALL4(mmu.ptep_modify_prot_commit, vma, addr, ptep, pte.pte);
439 }
440 
441 static inline void set_pte(pte_t *ptep, pte_t pte)
442 {
443 	PVOP_VCALL2(mmu.set_pte, ptep, pte.pte);
444 }
445 
446 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
447 {
448 	PVOP_VCALL2(mmu.set_pmd, pmdp, native_pmd_val(pmd));
449 }
450 
451 static inline pmd_t __pmd(pmdval_t val)
452 {
453 	return (pmd_t) { PVOP_ALT_CALLEE1(pmdval_t, mmu.make_pmd, val,
454 					  "mov %%rdi, %%rax",
455 					  ALT_NOT(X86_FEATURE_XENPV)) };
456 }
457 
458 static inline pmdval_t pmd_val(pmd_t pmd)
459 {
460 	return PVOP_ALT_CALLEE1(pmdval_t, mmu.pmd_val, pmd.pmd,
461 				"mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
462 }
463 
464 static inline void set_pud(pud_t *pudp, pud_t pud)
465 {
466 	PVOP_VCALL2(mmu.set_pud, pudp, native_pud_val(pud));
467 }
468 
469 static inline pud_t __pud(pudval_t val)
470 {
471 	pudval_t ret;
472 
473 	ret = PVOP_ALT_CALLEE1(pudval_t, mmu.make_pud, val,
474 			       "mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
475 
476 	return (pud_t) { ret };
477 }
478 
479 static inline pudval_t pud_val(pud_t pud)
480 {
481 	return PVOP_ALT_CALLEE1(pudval_t, mmu.pud_val, pud.pud,
482 				"mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
483 }
484 
485 static inline void pud_clear(pud_t *pudp)
486 {
487 	set_pud(pudp, native_make_pud(0));
488 }
489 
490 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
491 {
492 	p4dval_t val = native_p4d_val(p4d);
493 
494 	PVOP_VCALL2(mmu.set_p4d, p4dp, val);
495 }
496 
497 #if CONFIG_PGTABLE_LEVELS >= 5
498 
499 static inline p4d_t __p4d(p4dval_t val)
500 {
501 	p4dval_t ret = PVOP_ALT_CALLEE1(p4dval_t, mmu.make_p4d, val,
502 					"mov %%rdi, %%rax",
503 					ALT_NOT(X86_FEATURE_XENPV));
504 
505 	return (p4d_t) { ret };
506 }
507 
508 static inline p4dval_t p4d_val(p4d_t p4d)
509 {
510 	return PVOP_ALT_CALLEE1(p4dval_t, mmu.p4d_val, p4d.p4d,
511 				"mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
512 }
513 
514 static inline void __set_pgd(pgd_t *pgdp, pgd_t pgd)
515 {
516 	PVOP_VCALL2(mmu.set_pgd, pgdp, native_pgd_val(pgd));
517 }
518 
519 #define set_pgd(pgdp, pgdval) do {					\
520 	if (pgtable_l5_enabled())						\
521 		__set_pgd(pgdp, pgdval);				\
522 	else								\
523 		set_p4d((p4d_t *)(pgdp), (p4d_t) { (pgdval).pgd });	\
524 } while (0)
525 
526 #define pgd_clear(pgdp) do {						\
527 	if (pgtable_l5_enabled())					\
528 		set_pgd(pgdp, native_make_pgd(0));			\
529 } while (0)
530 
531 #endif  /* CONFIG_PGTABLE_LEVELS == 5 */
532 
533 static inline void p4d_clear(p4d_t *p4dp)
534 {
535 	set_p4d(p4dp, native_make_p4d(0));
536 }
537 
538 static inline void set_pte_atomic(pte_t *ptep, pte_t pte)
539 {
540 	set_pte(ptep, pte);
541 }
542 
543 static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
544 			     pte_t *ptep)
545 {
546 	set_pte(ptep, native_make_pte(0));
547 }
548 
549 static inline void pmd_clear(pmd_t *pmdp)
550 {
551 	set_pmd(pmdp, native_make_pmd(0));
552 }
553 
554 #define  __HAVE_ARCH_START_CONTEXT_SWITCH
555 static inline void arch_start_context_switch(struct task_struct *prev)
556 {
557 	PVOP_VCALL1(cpu.start_context_switch, prev);
558 }
559 
560 static inline void arch_end_context_switch(struct task_struct *next)
561 {
562 	PVOP_VCALL1(cpu.end_context_switch, next);
563 }
564 
565 #define  __HAVE_ARCH_ENTER_LAZY_MMU_MODE
566 static inline void arch_enter_lazy_mmu_mode(void)
567 {
568 	PVOP_VCALL0(mmu.lazy_mode.enter);
569 }
570 
571 static inline void arch_leave_lazy_mmu_mode(void)
572 {
573 	PVOP_VCALL0(mmu.lazy_mode.leave);
574 }
575 
576 static inline void arch_flush_lazy_mmu_mode(void)
577 {
578 	PVOP_VCALL0(mmu.lazy_mode.flush);
579 }
580 
581 static inline void __set_fixmap(unsigned /* enum fixed_addresses */ idx,
582 				phys_addr_t phys, pgprot_t flags)
583 {
584 	pv_ops.mmu.set_fixmap(idx, phys, flags);
585 }
586 #endif
587 
588 #if defined(CONFIG_SMP) && defined(CONFIG_PARAVIRT_SPINLOCKS)
589 
590 static __always_inline void pv_queued_spin_lock_slowpath(struct qspinlock *lock,
591 							u32 val)
592 {
593 	PVOP_VCALL2(lock.queued_spin_lock_slowpath, lock, val);
594 }
595 
596 static __always_inline void pv_queued_spin_unlock(struct qspinlock *lock)
597 {
598 	PVOP_ALT_VCALLEE1(lock.queued_spin_unlock, lock,
599 			  "movb $0, (%%" _ASM_ARG1 ");",
600 			  ALT_NOT(X86_FEATURE_PVUNLOCK));
601 }
602 
603 static __always_inline void pv_wait(u8 *ptr, u8 val)
604 {
605 	PVOP_VCALL2(lock.wait, ptr, val);
606 }
607 
608 static __always_inline void pv_kick(int cpu)
609 {
610 	PVOP_VCALL1(lock.kick, cpu);
611 }
612 
613 static __always_inline bool pv_vcpu_is_preempted(long cpu)
614 {
615 	return PVOP_ALT_CALLEE1(bool, lock.vcpu_is_preempted, cpu,
616 				"xor %%" _ASM_AX ", %%" _ASM_AX ";",
617 				ALT_NOT(X86_FEATURE_VCPUPREEMPT));
618 }
619 
620 void __raw_callee_save___native_queued_spin_unlock(struct qspinlock *lock);
621 bool __raw_callee_save___native_vcpu_is_preempted(long cpu);
622 
623 #endif /* SMP && PARAVIRT_SPINLOCKS */
624 
625 #ifdef CONFIG_X86_32
626 /* save and restore all caller-save registers, except return value */
627 #define PV_SAVE_ALL_CALLER_REGS		"pushl %ecx;"
628 #define PV_RESTORE_ALL_CALLER_REGS	"popl  %ecx;"
629 #else
630 /* save and restore all caller-save registers, except return value */
631 #define PV_SAVE_ALL_CALLER_REGS						\
632 	"push %rcx;"							\
633 	"push %rdx;"							\
634 	"push %rsi;"							\
635 	"push %rdi;"							\
636 	"push %r8;"							\
637 	"push %r9;"							\
638 	"push %r10;"							\
639 	"push %r11;"
640 #define PV_RESTORE_ALL_CALLER_REGS					\
641 	"pop %r11;"							\
642 	"pop %r10;"							\
643 	"pop %r9;"							\
644 	"pop %r8;"							\
645 	"pop %rdi;"							\
646 	"pop %rsi;"							\
647 	"pop %rdx;"							\
648 	"pop %rcx;"
649 #endif
650 
651 /*
652  * Generate a thunk around a function which saves all caller-save
653  * registers except for the return value.  This allows C functions to
654  * be called from assembler code where fewer than normal registers are
655  * available.  It may also help code generation around calls from C
656  * code if the common case doesn't use many registers.
657  *
658  * When a callee is wrapped in a thunk, the caller can assume that all
659  * arg regs and all scratch registers are preserved across the
660  * call. The return value in rax/eax will not be saved, even for void
661  * functions.
662  */
663 #define PV_THUNK_NAME(func) "__raw_callee_save_" #func
664 #define __PV_CALLEE_SAVE_REGS_THUNK(func, section)			\
665 	extern typeof(func) __raw_callee_save_##func;			\
666 									\
667 	asm(".pushsection " section ", \"ax\";"				\
668 	    ".globl " PV_THUNK_NAME(func) ";"				\
669 	    ".type " PV_THUNK_NAME(func) ", @function;"			\
670 	    ASM_FUNC_ALIGN						\
671 	    PV_THUNK_NAME(func) ":"					\
672 	    ASM_ENDBR							\
673 	    FRAME_BEGIN							\
674 	    PV_SAVE_ALL_CALLER_REGS					\
675 	    "call " #func ";"						\
676 	    PV_RESTORE_ALL_CALLER_REGS					\
677 	    FRAME_END							\
678 	    ASM_RET							\
679 	    ".size " PV_THUNK_NAME(func) ", .-" PV_THUNK_NAME(func) ";"	\
680 	    ".popsection")
681 
682 #define PV_CALLEE_SAVE_REGS_THUNK(func)			\
683 	__PV_CALLEE_SAVE_REGS_THUNK(func, ".text")
684 
685 /* Get a reference to a callee-save function */
686 #define PV_CALLEE_SAVE(func)						\
687 	((struct paravirt_callee_save) { __raw_callee_save_##func })
688 
689 /* Promise that "func" already uses the right calling convention */
690 #define __PV_IS_CALLEE_SAVE(func)			\
691 	((struct paravirt_callee_save) { func })
692 
693 #ifdef CONFIG_PARAVIRT_XXL
694 static __always_inline unsigned long arch_local_save_flags(void)
695 {
696 	return PVOP_ALT_CALLEE0(unsigned long, irq.save_fl, "pushf; pop %%rax;",
697 				ALT_NOT(X86_FEATURE_XENPV));
698 }
699 
700 static __always_inline void arch_local_irq_disable(void)
701 {
702 	PVOP_ALT_VCALLEE0(irq.irq_disable, "cli;", ALT_NOT(X86_FEATURE_XENPV));
703 }
704 
705 static __always_inline void arch_local_irq_enable(void)
706 {
707 	PVOP_ALT_VCALLEE0(irq.irq_enable, "sti;", ALT_NOT(X86_FEATURE_XENPV));
708 }
709 
710 static __always_inline unsigned long arch_local_irq_save(void)
711 {
712 	unsigned long f;
713 
714 	f = arch_local_save_flags();
715 	arch_local_irq_disable();
716 	return f;
717 }
718 #endif
719 
720 
721 /* Make sure as little as possible of this mess escapes. */
722 #undef PARAVIRT_CALL
723 #undef __PVOP_CALL
724 #undef __PVOP_VCALL
725 #undef PVOP_VCALL0
726 #undef PVOP_CALL0
727 #undef PVOP_VCALL1
728 #undef PVOP_CALL1
729 #undef PVOP_VCALL2
730 #undef PVOP_CALL2
731 #undef PVOP_VCALL3
732 #undef PVOP_CALL3
733 #undef PVOP_VCALL4
734 #undef PVOP_CALL4
735 
736 #define DEFINE_PARAVIRT_ASM(func, instr, sec)		\
737 	asm (".pushsection " #sec ", \"ax\"\n"		\
738 	     ".global " #func "\n\t"			\
739 	     ".type " #func ", @function\n\t"		\
740 	     ASM_FUNC_ALIGN "\n"			\
741 	     #func ":\n\t"				\
742 	     ASM_ENDBR					\
743 	     instr "\n\t"				\
744 	     ASM_RET					\
745 	     ".size " #func ", . - " #func "\n\t"	\
746 	     ".popsection")
747 
748 extern void default_banner(void);
749 
750 #else  /* __ASSEMBLY__ */
751 
752 #define _PVSITE(ptype, ops, word, algn)		\
753 771:;						\
754 	ops;					\
755 772:;						\
756 	.pushsection .parainstructions,"a";	\
757 	 .align	algn;				\
758 	 word 771b;				\
759 	 .byte ptype;				\
760 	 .byte 772b-771b;			\
761 	 _ASM_ALIGN;				\
762 	.popsection
763 
764 
765 #ifdef CONFIG_X86_64
766 #ifdef CONFIG_PARAVIRT_XXL
767 
768 #define PARA_PATCH(off)		((off) / 8)
769 #define PARA_SITE(ptype, ops)	_PVSITE(ptype, ops, .quad, 8)
770 #define PARA_INDIRECT(addr)	*addr(%rip)
771 
772 #ifdef CONFIG_DEBUG_ENTRY
773 .macro PARA_IRQ_save_fl
774 	PARA_SITE(PARA_PATCH(PV_IRQ_save_fl),
775 		  ANNOTATE_RETPOLINE_SAFE;
776 		  call PARA_INDIRECT(pv_ops+PV_IRQ_save_fl);)
777 .endm
778 
779 #define SAVE_FLAGS	ALTERNATIVE "PARA_IRQ_save_fl;", "pushf; pop %rax;", \
780 				    ALT_NOT(X86_FEATURE_XENPV)
781 #endif
782 #endif /* CONFIG_PARAVIRT_XXL */
783 #endif	/* CONFIG_X86_64 */
784 
785 #endif /* __ASSEMBLY__ */
786 #else  /* CONFIG_PARAVIRT */
787 # define default_banner x86_init_noop
788 #endif /* !CONFIG_PARAVIRT */
789 
790 #ifndef __ASSEMBLY__
791 #ifndef CONFIG_PARAVIRT_XXL
792 static inline void paravirt_arch_dup_mmap(struct mm_struct *oldmm,
793 					  struct mm_struct *mm)
794 {
795 }
796 #endif
797 
798 #ifndef CONFIG_PARAVIRT
799 static inline void paravirt_arch_exit_mmap(struct mm_struct *mm)
800 {
801 }
802 #endif
803 
804 #ifndef CONFIG_PARAVIRT_SPINLOCKS
805 static inline void paravirt_set_cap(void)
806 {
807 }
808 #endif
809 #endif /* __ASSEMBLY__ */
810 #endif /* _ASM_X86_PARAVIRT_H */
811