xref: /linux/arch/x86/include/asm/paravirt.h (revision 41e0d49104dbff888ef6446ea46842fde66c0a76)
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 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 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 static inline void wbinvd(void)
182 {
183 	PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", ALT_NOT(X86_FEATURE_XENPV));
184 }
185 
186 static inline u64 paravirt_read_msr(unsigned msr)
187 {
188 	return PVOP_CALL1(u64, cpu.read_msr, msr);
189 }
190 
191 static inline void paravirt_write_msr(unsigned msr,
192 				      unsigned low, unsigned high)
193 {
194 	PVOP_VCALL3(cpu.write_msr, msr, low, high);
195 }
196 
197 static inline u64 paravirt_read_msr_safe(unsigned msr, int *err)
198 {
199 	return PVOP_CALL2(u64, cpu.read_msr_safe, msr, err);
200 }
201 
202 static inline int paravirt_write_msr_safe(unsigned msr,
203 					  unsigned low, unsigned high)
204 {
205 	return PVOP_CALL3(int, cpu.write_msr_safe, msr, low, high);
206 }
207 
208 #define rdmsr(msr, val1, val2)			\
209 do {						\
210 	u64 _l = paravirt_read_msr(msr);	\
211 	val1 = (u32)_l;				\
212 	val2 = _l >> 32;			\
213 } while (0)
214 
215 #define wrmsr(msr, val1, val2)			\
216 do {						\
217 	paravirt_write_msr(msr, val1, val2);	\
218 } while (0)
219 
220 #define rdmsrl(msr, val)			\
221 do {						\
222 	val = paravirt_read_msr(msr);		\
223 } while (0)
224 
225 static inline void wrmsrl(unsigned msr, u64 val)
226 {
227 	wrmsr(msr, (u32)val, (u32)(val>>32));
228 }
229 
230 #define wrmsr_safe(msr, a, b)	paravirt_write_msr_safe(msr, a, b)
231 
232 /* rdmsr with exception handling */
233 #define rdmsr_safe(msr, a, b)				\
234 ({							\
235 	int _err;					\
236 	u64 _l = paravirt_read_msr_safe(msr, &_err);	\
237 	(*a) = (u32)_l;					\
238 	(*b) = _l >> 32;				\
239 	_err;						\
240 })
241 
242 static inline int rdmsrl_safe(unsigned msr, unsigned long long *p)
243 {
244 	int err;
245 
246 	*p = paravirt_read_msr_safe(msr, &err);
247 	return err;
248 }
249 
250 static inline unsigned long long paravirt_read_pmc(int counter)
251 {
252 	return PVOP_CALL1(u64, cpu.read_pmc, counter);
253 }
254 
255 #define rdpmc(counter, low, high)		\
256 do {						\
257 	u64 _l = paravirt_read_pmc(counter);	\
258 	low = (u32)_l;				\
259 	high = _l >> 32;			\
260 } while (0)
261 
262 #define rdpmcl(counter, val) ((val) = paravirt_read_pmc(counter))
263 
264 static inline void paravirt_alloc_ldt(struct desc_struct *ldt, unsigned entries)
265 {
266 	PVOP_VCALL2(cpu.alloc_ldt, ldt, entries);
267 }
268 
269 static inline void paravirt_free_ldt(struct desc_struct *ldt, unsigned entries)
270 {
271 	PVOP_VCALL2(cpu.free_ldt, ldt, entries);
272 }
273 
274 static inline void load_TR_desc(void)
275 {
276 	PVOP_VCALL0(cpu.load_tr_desc);
277 }
278 static inline void load_gdt(const struct desc_ptr *dtr)
279 {
280 	PVOP_VCALL1(cpu.load_gdt, dtr);
281 }
282 static inline void load_idt(const struct desc_ptr *dtr)
283 {
284 	PVOP_VCALL1(cpu.load_idt, dtr);
285 }
286 static inline void set_ldt(const void *addr, unsigned entries)
287 {
288 	PVOP_VCALL2(cpu.set_ldt, addr, entries);
289 }
290 static inline unsigned long paravirt_store_tr(void)
291 {
292 	return PVOP_CALL0(unsigned long, cpu.store_tr);
293 }
294 
295 #define store_tr(tr)	((tr) = paravirt_store_tr())
296 static inline void load_TLS(struct thread_struct *t, unsigned cpu)
297 {
298 	PVOP_VCALL2(cpu.load_tls, t, cpu);
299 }
300 
301 static inline void load_gs_index(unsigned int gs)
302 {
303 	PVOP_VCALL1(cpu.load_gs_index, gs);
304 }
305 
306 static inline void write_ldt_entry(struct desc_struct *dt, int entry,
307 				   const void *desc)
308 {
309 	PVOP_VCALL3(cpu.write_ldt_entry, dt, entry, desc);
310 }
311 
312 static inline void write_gdt_entry(struct desc_struct *dt, int entry,
313 				   void *desc, int type)
314 {
315 	PVOP_VCALL4(cpu.write_gdt_entry, dt, entry, desc, type);
316 }
317 
318 static inline void write_idt_entry(gate_desc *dt, int entry, const gate_desc *g)
319 {
320 	PVOP_VCALL3(cpu.write_idt_entry, dt, entry, g);
321 }
322 
323 #ifdef CONFIG_X86_IOPL_IOPERM
324 static inline void tss_invalidate_io_bitmap(void)
325 {
326 	PVOP_VCALL0(cpu.invalidate_io_bitmap);
327 }
328 
329 static inline void tss_update_io_bitmap(void)
330 {
331 	PVOP_VCALL0(cpu.update_io_bitmap);
332 }
333 #endif
334 
335 static inline void paravirt_activate_mm(struct mm_struct *prev,
336 					struct mm_struct *next)
337 {
338 	PVOP_VCALL2(mmu.activate_mm, prev, next);
339 }
340 
341 static inline void paravirt_arch_dup_mmap(struct mm_struct *oldmm,
342 					  struct mm_struct *mm)
343 {
344 	PVOP_VCALL2(mmu.dup_mmap, oldmm, mm);
345 }
346 
347 static inline int paravirt_pgd_alloc(struct mm_struct *mm)
348 {
349 	return PVOP_CALL1(int, mmu.pgd_alloc, mm);
350 }
351 
352 static inline void paravirt_pgd_free(struct mm_struct *mm, pgd_t *pgd)
353 {
354 	PVOP_VCALL2(mmu.pgd_free, mm, pgd);
355 }
356 
357 static inline void paravirt_alloc_pte(struct mm_struct *mm, unsigned long pfn)
358 {
359 	PVOP_VCALL2(mmu.alloc_pte, mm, pfn);
360 }
361 static inline void paravirt_release_pte(unsigned long pfn)
362 {
363 	PVOP_VCALL1(mmu.release_pte, pfn);
364 }
365 
366 static inline void paravirt_alloc_pmd(struct mm_struct *mm, unsigned long pfn)
367 {
368 	PVOP_VCALL2(mmu.alloc_pmd, mm, pfn);
369 }
370 
371 static inline void paravirt_release_pmd(unsigned long pfn)
372 {
373 	PVOP_VCALL1(mmu.release_pmd, pfn);
374 }
375 
376 static inline void paravirt_alloc_pud(struct mm_struct *mm, unsigned long pfn)
377 {
378 	PVOP_VCALL2(mmu.alloc_pud, mm, pfn);
379 }
380 static inline void paravirt_release_pud(unsigned long pfn)
381 {
382 	PVOP_VCALL1(mmu.release_pud, pfn);
383 }
384 
385 static inline void paravirt_alloc_p4d(struct mm_struct *mm, unsigned long pfn)
386 {
387 	PVOP_VCALL2(mmu.alloc_p4d, mm, pfn);
388 }
389 
390 static inline void paravirt_release_p4d(unsigned long pfn)
391 {
392 	PVOP_VCALL1(mmu.release_p4d, pfn);
393 }
394 
395 static inline pte_t __pte(pteval_t val)
396 {
397 	return (pte_t) { PVOP_ALT_CALLEE1(pteval_t, mmu.make_pte, val,
398 					  "mov %%rdi, %%rax",
399 					  ALT_NOT(X86_FEATURE_XENPV)) };
400 }
401 
402 static inline pteval_t pte_val(pte_t pte)
403 {
404 	return PVOP_ALT_CALLEE1(pteval_t, mmu.pte_val, pte.pte,
405 				"mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
406 }
407 
408 static inline pgd_t __pgd(pgdval_t val)
409 {
410 	return (pgd_t) { PVOP_ALT_CALLEE1(pgdval_t, mmu.make_pgd, val,
411 					  "mov %%rdi, %%rax",
412 					  ALT_NOT(X86_FEATURE_XENPV)) };
413 }
414 
415 static inline pgdval_t pgd_val(pgd_t pgd)
416 {
417 	return PVOP_ALT_CALLEE1(pgdval_t, mmu.pgd_val, pgd.pgd,
418 				"mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
419 }
420 
421 #define  __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
422 static inline pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr,
423 					   pte_t *ptep)
424 {
425 	pteval_t ret;
426 
427 	ret = PVOP_CALL3(pteval_t, mmu.ptep_modify_prot_start, vma, addr, ptep);
428 
429 	return (pte_t) { .pte = ret };
430 }
431 
432 static inline void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
433 					   pte_t *ptep, pte_t old_pte, pte_t pte)
434 {
435 
436 	PVOP_VCALL4(mmu.ptep_modify_prot_commit, vma, addr, ptep, pte.pte);
437 }
438 
439 static inline void set_pte(pte_t *ptep, pte_t pte)
440 {
441 	PVOP_VCALL2(mmu.set_pte, ptep, pte.pte);
442 }
443 
444 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
445 {
446 	PVOP_VCALL2(mmu.set_pmd, pmdp, native_pmd_val(pmd));
447 }
448 
449 static inline pmd_t __pmd(pmdval_t val)
450 {
451 	return (pmd_t) { PVOP_ALT_CALLEE1(pmdval_t, mmu.make_pmd, val,
452 					  "mov %%rdi, %%rax",
453 					  ALT_NOT(X86_FEATURE_XENPV)) };
454 }
455 
456 static inline pmdval_t pmd_val(pmd_t pmd)
457 {
458 	return PVOP_ALT_CALLEE1(pmdval_t, mmu.pmd_val, pmd.pmd,
459 				"mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
460 }
461 
462 static inline void set_pud(pud_t *pudp, pud_t pud)
463 {
464 	PVOP_VCALL2(mmu.set_pud, pudp, native_pud_val(pud));
465 }
466 
467 static inline pud_t __pud(pudval_t val)
468 {
469 	pudval_t ret;
470 
471 	ret = PVOP_ALT_CALLEE1(pudval_t, mmu.make_pud, val,
472 			       "mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
473 
474 	return (pud_t) { ret };
475 }
476 
477 static inline pudval_t pud_val(pud_t pud)
478 {
479 	return PVOP_ALT_CALLEE1(pudval_t, mmu.pud_val, pud.pud,
480 				"mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
481 }
482 
483 static inline void pud_clear(pud_t *pudp)
484 {
485 	set_pud(pudp, native_make_pud(0));
486 }
487 
488 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
489 {
490 	p4dval_t val = native_p4d_val(p4d);
491 
492 	PVOP_VCALL2(mmu.set_p4d, p4dp, val);
493 }
494 
495 #if CONFIG_PGTABLE_LEVELS >= 5
496 
497 static inline p4d_t __p4d(p4dval_t val)
498 {
499 	p4dval_t ret = PVOP_ALT_CALLEE1(p4dval_t, mmu.make_p4d, val,
500 					"mov %%rdi, %%rax",
501 					ALT_NOT(X86_FEATURE_XENPV));
502 
503 	return (p4d_t) { ret };
504 }
505 
506 static inline p4dval_t p4d_val(p4d_t p4d)
507 {
508 	return PVOP_ALT_CALLEE1(p4dval_t, mmu.p4d_val, p4d.p4d,
509 				"mov %%rdi, %%rax", ALT_NOT(X86_FEATURE_XENPV));
510 }
511 
512 static inline void __set_pgd(pgd_t *pgdp, pgd_t pgd)
513 {
514 	PVOP_VCALL2(mmu.set_pgd, pgdp, native_pgd_val(pgd));
515 }
516 
517 #define set_pgd(pgdp, pgdval) do {					\
518 	if (pgtable_l5_enabled())						\
519 		__set_pgd(pgdp, pgdval);				\
520 	else								\
521 		set_p4d((p4d_t *)(pgdp), (p4d_t) { (pgdval).pgd });	\
522 } while (0)
523 
524 #define pgd_clear(pgdp) do {						\
525 	if (pgtable_l5_enabled())					\
526 		set_pgd(pgdp, native_make_pgd(0));			\
527 } while (0)
528 
529 #endif  /* CONFIG_PGTABLE_LEVELS == 5 */
530 
531 static inline void p4d_clear(p4d_t *p4dp)
532 {
533 	set_p4d(p4dp, native_make_p4d(0));
534 }
535 
536 static inline void set_pte_atomic(pte_t *ptep, pte_t pte)
537 {
538 	set_pte(ptep, pte);
539 }
540 
541 static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
542 			     pte_t *ptep)
543 {
544 	set_pte(ptep, native_make_pte(0));
545 }
546 
547 static inline void pmd_clear(pmd_t *pmdp)
548 {
549 	set_pmd(pmdp, native_make_pmd(0));
550 }
551 
552 #define  __HAVE_ARCH_START_CONTEXT_SWITCH
553 static inline void arch_start_context_switch(struct task_struct *prev)
554 {
555 	PVOP_VCALL1(cpu.start_context_switch, prev);
556 }
557 
558 static inline void arch_end_context_switch(struct task_struct *next)
559 {
560 	PVOP_VCALL1(cpu.end_context_switch, next);
561 }
562 
563 #define  __HAVE_ARCH_ENTER_LAZY_MMU_MODE
564 static inline void arch_enter_lazy_mmu_mode(void)
565 {
566 	PVOP_VCALL0(mmu.lazy_mode.enter);
567 }
568 
569 static inline void arch_leave_lazy_mmu_mode(void)
570 {
571 	PVOP_VCALL0(mmu.lazy_mode.leave);
572 }
573 
574 static inline void arch_flush_lazy_mmu_mode(void)
575 {
576 	PVOP_VCALL0(mmu.lazy_mode.flush);
577 }
578 
579 static inline void __set_fixmap(unsigned /* enum fixed_addresses */ idx,
580 				phys_addr_t phys, pgprot_t flags)
581 {
582 	pv_ops.mmu.set_fixmap(idx, phys, flags);
583 }
584 #endif
585 
586 #if defined(CONFIG_SMP) && defined(CONFIG_PARAVIRT_SPINLOCKS)
587 
588 static __always_inline void pv_queued_spin_lock_slowpath(struct qspinlock *lock,
589 							u32 val)
590 {
591 	PVOP_VCALL2(lock.queued_spin_lock_slowpath, lock, val);
592 }
593 
594 static __always_inline void pv_queued_spin_unlock(struct qspinlock *lock)
595 {
596 	PVOP_ALT_VCALLEE1(lock.queued_spin_unlock, lock,
597 			  "movb $0, (%%" _ASM_ARG1 ");",
598 			  ALT_NOT(X86_FEATURE_PVUNLOCK));
599 }
600 
601 static __always_inline void pv_wait(u8 *ptr, u8 val)
602 {
603 	PVOP_VCALL2(lock.wait, ptr, val);
604 }
605 
606 static __always_inline void pv_kick(int cpu)
607 {
608 	PVOP_VCALL1(lock.kick, cpu);
609 }
610 
611 static __always_inline bool pv_vcpu_is_preempted(long cpu)
612 {
613 	return PVOP_ALT_CALLEE1(bool, lock.vcpu_is_preempted, cpu,
614 				"xor %%" _ASM_AX ", %%" _ASM_AX ";",
615 				ALT_NOT(X86_FEATURE_VCPUPREEMPT));
616 }
617 
618 void __raw_callee_save___native_queued_spin_unlock(struct qspinlock *lock);
619 bool __raw_callee_save___native_vcpu_is_preempted(long cpu);
620 
621 #endif /* SMP && PARAVIRT_SPINLOCKS */
622 
623 #ifdef CONFIG_X86_32
624 /* save and restore all caller-save registers, except return value */
625 #define PV_SAVE_ALL_CALLER_REGS		"pushl %ecx;"
626 #define PV_RESTORE_ALL_CALLER_REGS	"popl  %ecx;"
627 #else
628 /* save and restore all caller-save registers, except return value */
629 #define PV_SAVE_ALL_CALLER_REGS						\
630 	"push %rcx;"							\
631 	"push %rdx;"							\
632 	"push %rsi;"							\
633 	"push %rdi;"							\
634 	"push %r8;"							\
635 	"push %r9;"							\
636 	"push %r10;"							\
637 	"push %r11;"
638 #define PV_RESTORE_ALL_CALLER_REGS					\
639 	"pop %r11;"							\
640 	"pop %r10;"							\
641 	"pop %r9;"							\
642 	"pop %r8;"							\
643 	"pop %rdi;"							\
644 	"pop %rsi;"							\
645 	"pop %rdx;"							\
646 	"pop %rcx;"
647 #endif
648 
649 /*
650  * Generate a thunk around a function which saves all caller-save
651  * registers except for the return value.  This allows C functions to
652  * be called from assembler code where fewer than normal registers are
653  * available.  It may also help code generation around calls from C
654  * code if the common case doesn't use many registers.
655  *
656  * When a callee is wrapped in a thunk, the caller can assume that all
657  * arg regs and all scratch registers are preserved across the
658  * call. The return value in rax/eax will not be saved, even for void
659  * functions.
660  */
661 #define PV_THUNK_NAME(func) "__raw_callee_save_" #func
662 #define __PV_CALLEE_SAVE_REGS_THUNK(func, section)			\
663 	extern typeof(func) __raw_callee_save_##func;			\
664 									\
665 	asm(".pushsection " section ", \"ax\";"				\
666 	    ".globl " PV_THUNK_NAME(func) ";"				\
667 	    ".type " PV_THUNK_NAME(func) ", @function;"			\
668 	    ASM_FUNC_ALIGN						\
669 	    PV_THUNK_NAME(func) ":"					\
670 	    ASM_ENDBR							\
671 	    FRAME_BEGIN							\
672 	    PV_SAVE_ALL_CALLER_REGS					\
673 	    "call " #func ";"						\
674 	    PV_RESTORE_ALL_CALLER_REGS					\
675 	    FRAME_END							\
676 	    ASM_RET							\
677 	    ".size " PV_THUNK_NAME(func) ", .-" PV_THUNK_NAME(func) ";"	\
678 	    ".popsection")
679 
680 #define PV_CALLEE_SAVE_REGS_THUNK(func)			\
681 	__PV_CALLEE_SAVE_REGS_THUNK(func, ".text")
682 
683 /* Get a reference to a callee-save function */
684 #define PV_CALLEE_SAVE(func)						\
685 	((struct paravirt_callee_save) { __raw_callee_save_##func })
686 
687 /* Promise that "func" already uses the right calling convention */
688 #define __PV_IS_CALLEE_SAVE(func)			\
689 	((struct paravirt_callee_save) { func })
690 
691 #ifdef CONFIG_PARAVIRT_XXL
692 static __always_inline unsigned long arch_local_save_flags(void)
693 {
694 	return PVOP_ALT_CALLEE0(unsigned long, irq.save_fl, "pushf; pop %%rax;",
695 				ALT_NOT(X86_FEATURE_XENPV));
696 }
697 
698 static __always_inline void arch_local_irq_disable(void)
699 {
700 	PVOP_ALT_VCALLEE0(irq.irq_disable, "cli;", ALT_NOT(X86_FEATURE_XENPV));
701 }
702 
703 static __always_inline void arch_local_irq_enable(void)
704 {
705 	PVOP_ALT_VCALLEE0(irq.irq_enable, "sti;", ALT_NOT(X86_FEATURE_XENPV));
706 }
707 
708 static __always_inline unsigned long arch_local_irq_save(void)
709 {
710 	unsigned long f;
711 
712 	f = arch_local_save_flags();
713 	arch_local_irq_disable();
714 	return f;
715 }
716 #endif
717 
718 
719 /* Make sure as little as possible of this mess escapes. */
720 #undef PARAVIRT_CALL
721 #undef __PVOP_CALL
722 #undef __PVOP_VCALL
723 #undef PVOP_VCALL0
724 #undef PVOP_CALL0
725 #undef PVOP_VCALL1
726 #undef PVOP_CALL1
727 #undef PVOP_VCALL2
728 #undef PVOP_CALL2
729 #undef PVOP_VCALL3
730 #undef PVOP_CALL3
731 #undef PVOP_VCALL4
732 #undef PVOP_CALL4
733 
734 #define DEFINE_PARAVIRT_ASM(func, instr, sec)		\
735 	asm (".pushsection " #sec ", \"ax\"\n"		\
736 	     ".global " #func "\n\t"			\
737 	     ".type " #func ", @function\n\t"		\
738 	     ASM_FUNC_ALIGN "\n"			\
739 	     #func ":\n\t"				\
740 	     ASM_ENDBR					\
741 	     instr "\n\t"				\
742 	     ASM_RET					\
743 	     ".size " #func ", . - " #func "\n\t"	\
744 	     ".popsection")
745 
746 extern void default_banner(void);
747 
748 #else  /* __ASSEMBLY__ */
749 
750 #define _PVSITE(ptype, ops, word, algn)		\
751 771:;						\
752 	ops;					\
753 772:;						\
754 	.pushsection .parainstructions,"a";	\
755 	 .align	algn;				\
756 	 word 771b;				\
757 	 .byte ptype;				\
758 	 .byte 772b-771b;			\
759 	 _ASM_ALIGN;				\
760 	.popsection
761 
762 
763 #ifdef CONFIG_X86_64
764 #ifdef CONFIG_PARAVIRT_XXL
765 
766 #define PARA_PATCH(off)		((off) / 8)
767 #define PARA_SITE(ptype, ops)	_PVSITE(ptype, ops, .quad, 8)
768 #define PARA_INDIRECT(addr)	*addr(%rip)
769 
770 #ifdef CONFIG_DEBUG_ENTRY
771 .macro PARA_IRQ_save_fl
772 	PARA_SITE(PARA_PATCH(PV_IRQ_save_fl),
773 		  ANNOTATE_RETPOLINE_SAFE;
774 		  call PARA_INDIRECT(pv_ops+PV_IRQ_save_fl);)
775 .endm
776 
777 #define SAVE_FLAGS	ALTERNATIVE "PARA_IRQ_save_fl;", "pushf; pop %rax;", \
778 				    ALT_NOT(X86_FEATURE_XENPV)
779 #endif
780 #endif /* CONFIG_PARAVIRT_XXL */
781 #endif	/* CONFIG_X86_64 */
782 
783 #endif /* __ASSEMBLY__ */
784 #else  /* CONFIG_PARAVIRT */
785 # define default_banner x86_init_noop
786 #endif /* !CONFIG_PARAVIRT */
787 
788 #ifndef __ASSEMBLY__
789 #ifndef CONFIG_PARAVIRT_XXL
790 static inline void paravirt_arch_dup_mmap(struct mm_struct *oldmm,
791 					  struct mm_struct *mm)
792 {
793 }
794 #endif
795 
796 #ifndef CONFIG_PARAVIRT
797 static inline void paravirt_arch_exit_mmap(struct mm_struct *mm)
798 {
799 }
800 #endif
801 
802 #ifndef CONFIG_PARAVIRT_SPINLOCKS
803 static inline void paravirt_set_cap(void)
804 {
805 }
806 #endif
807 #endif /* __ASSEMBLY__ */
808 #endif /* _ASM_X86_PARAVIRT_H */
809