1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_PARAVIRT_TYPES_H
3 #define _ASM_X86_PARAVIRT_TYPES_H
4 
5 #ifdef CONFIG_PARAVIRT
6 
7 #ifndef __ASSEMBLY__
8 #include <linux/types.h>
9 
10 #include <asm/desc_defs.h>
11 #include <asm/pgtable_types.h>
12 #include <asm/nospec-branch.h>
13 
14 struct page;
15 struct thread_struct;
16 struct desc_ptr;
17 struct tss_struct;
18 struct mm_struct;
19 struct desc_struct;
20 struct task_struct;
21 struct cpumask;
22 struct flush_tlb_info;
23 struct mmu_gather;
24 struct vm_area_struct;
25 
26 /*
27  * Wrapper type for pointers to code which uses the non-standard
28  * calling convention.  See PV_CALL_SAVE_REGS_THUNK below.
29  */
30 struct paravirt_callee_save {
31 	void *func;
32 };
33 
34 /* general info */
35 struct pv_info {
36 #ifdef CONFIG_PARAVIRT_XXL
37 	u16 extra_user_64bit_cs;  /* __USER_CS if none */
38 #endif
39 
40 	const char *name;
41 };
42 
43 #ifdef CONFIG_PARAVIRT_XXL
44 struct pv_lazy_ops {
45 	/* Set deferred update mode, used for batching operations. */
46 	void (*enter)(void);
47 	void (*leave)(void);
48 	void (*flush)(void);
49 } __no_randomize_layout;
50 #endif
51 
52 struct pv_cpu_ops {
53 	/* hooks for various privileged instructions */
54 	void (*io_delay)(void);
55 
56 #ifdef CONFIG_PARAVIRT_XXL
57 	unsigned long (*get_debugreg)(int regno);
58 	void (*set_debugreg)(int regno, unsigned long value);
59 
60 	unsigned long (*read_cr0)(void);
61 	void (*write_cr0)(unsigned long);
62 
63 	void (*write_cr4)(unsigned long);
64 
65 	/* Segment descriptor handling */
66 	void (*load_tr_desc)(void);
67 	void (*load_gdt)(const struct desc_ptr *);
68 	void (*load_idt)(const struct desc_ptr *);
69 	void (*set_ldt)(const void *desc, unsigned entries);
70 	unsigned long (*store_tr)(void);
71 	void (*load_tls)(struct thread_struct *t, unsigned int cpu);
72 	void (*load_gs_index)(unsigned int idx);
73 	void (*write_ldt_entry)(struct desc_struct *ldt, int entrynum,
74 				const void *desc);
75 	void (*write_gdt_entry)(struct desc_struct *,
76 				int entrynum, const void *desc, int size);
77 	void (*write_idt_entry)(gate_desc *,
78 				int entrynum, const gate_desc *gate);
79 	void (*alloc_ldt)(struct desc_struct *ldt, unsigned entries);
80 	void (*free_ldt)(struct desc_struct *ldt, unsigned entries);
81 
82 	void (*load_sp0)(unsigned long sp0);
83 
84 #ifdef CONFIG_X86_IOPL_IOPERM
85 	void (*invalidate_io_bitmap)(void);
86 	void (*update_io_bitmap)(void);
87 #endif
88 
89 	/* cpuid emulation, mostly so that caps bits can be disabled */
90 	void (*cpuid)(unsigned int *eax, unsigned int *ebx,
91 		      unsigned int *ecx, unsigned int *edx);
92 
93 	/* Unsafe MSR operations.  These will warn or panic on failure. */
94 	u64 (*read_msr)(unsigned int msr);
95 	void (*write_msr)(unsigned int msr, unsigned low, unsigned high);
96 
97 	/*
98 	 * Safe MSR operations.
99 	 * read sets err to 0 or -EIO.  write returns 0 or -EIO.
100 	 */
101 	u64 (*read_msr_safe)(unsigned int msr, int *err);
102 	int (*write_msr_safe)(unsigned int msr, unsigned low, unsigned high);
103 
104 	u64 (*read_pmc)(int counter);
105 
106 	void (*start_context_switch)(struct task_struct *prev);
107 	void (*end_context_switch)(struct task_struct *next);
108 #endif
109 } __no_randomize_layout;
110 
111 struct pv_irq_ops {
112 #ifdef CONFIG_PARAVIRT_XXL
113 	/*
114 	 * Get/set interrupt state.  save_fl is expected to use X86_EFLAGS_IF;
115 	 * all other bits returned from save_fl are undefined.
116 	 *
117 	 * NOTE: These functions callers expect the callee to preserve
118 	 * more registers than the standard C calling convention.
119 	 */
120 	struct paravirt_callee_save save_fl;
121 	struct paravirt_callee_save irq_disable;
122 	struct paravirt_callee_save irq_enable;
123 #endif
124 	void (*safe_halt)(void);
125 	void (*halt)(void);
126 } __no_randomize_layout;
127 
128 struct pv_mmu_ops {
129 	/* TLB operations */
130 	void (*flush_tlb_user)(void);
131 	void (*flush_tlb_kernel)(void);
132 	void (*flush_tlb_one_user)(unsigned long addr);
133 	void (*flush_tlb_multi)(const struct cpumask *cpus,
134 				const struct flush_tlb_info *info);
135 
136 	void (*tlb_remove_table)(struct mmu_gather *tlb, void *table);
137 
138 	/* Hook for intercepting the destruction of an mm_struct. */
139 	void (*exit_mmap)(struct mm_struct *mm);
140 	void (*notify_page_enc_status_changed)(unsigned long pfn, int npages, bool enc);
141 
142 #ifdef CONFIG_PARAVIRT_XXL
143 	struct paravirt_callee_save read_cr2;
144 	void (*write_cr2)(unsigned long);
145 
146 	unsigned long (*read_cr3)(void);
147 	void (*write_cr3)(unsigned long);
148 
149 	/* Hook for intercepting the creation/use of an mm_struct. */
150 	void (*enter_mmap)(struct mm_struct *mm);
151 
152 	/* Hooks for allocating and freeing a pagetable top-level */
153 	int  (*pgd_alloc)(struct mm_struct *mm);
154 	void (*pgd_free)(struct mm_struct *mm, pgd_t *pgd);
155 
156 	/*
157 	 * Hooks for allocating/releasing pagetable pages when they're
158 	 * attached to a pagetable
159 	 */
160 	void (*alloc_pte)(struct mm_struct *mm, unsigned long pfn);
161 	void (*alloc_pmd)(struct mm_struct *mm, unsigned long pfn);
162 	void (*alloc_pud)(struct mm_struct *mm, unsigned long pfn);
163 	void (*alloc_p4d)(struct mm_struct *mm, unsigned long pfn);
164 	void (*release_pte)(unsigned long pfn);
165 	void (*release_pmd)(unsigned long pfn);
166 	void (*release_pud)(unsigned long pfn);
167 	void (*release_p4d)(unsigned long pfn);
168 
169 	/* Pagetable manipulation functions */
170 	void (*set_pte)(pte_t *ptep, pte_t pteval);
171 	void (*set_pmd)(pmd_t *pmdp, pmd_t pmdval);
172 
173 	pte_t (*ptep_modify_prot_start)(struct vm_area_struct *vma, unsigned long addr,
174 					pte_t *ptep);
175 	void (*ptep_modify_prot_commit)(struct vm_area_struct *vma, unsigned long addr,
176 					pte_t *ptep, pte_t pte);
177 
178 	struct paravirt_callee_save pte_val;
179 	struct paravirt_callee_save make_pte;
180 
181 	struct paravirt_callee_save pgd_val;
182 	struct paravirt_callee_save make_pgd;
183 
184 	void (*set_pud)(pud_t *pudp, pud_t pudval);
185 
186 	struct paravirt_callee_save pmd_val;
187 	struct paravirt_callee_save make_pmd;
188 
189 	struct paravirt_callee_save pud_val;
190 	struct paravirt_callee_save make_pud;
191 
192 	void (*set_p4d)(p4d_t *p4dp, p4d_t p4dval);
193 
194 #if CONFIG_PGTABLE_LEVELS >= 5
195 	struct paravirt_callee_save p4d_val;
196 	struct paravirt_callee_save make_p4d;
197 
198 	void (*set_pgd)(pgd_t *pgdp, pgd_t pgdval);
199 #endif	/* CONFIG_PGTABLE_LEVELS >= 5 */
200 
201 	struct pv_lazy_ops lazy_mode;
202 
203 	/* dom0 ops */
204 
205 	/* Sometimes the physical address is a pfn, and sometimes its
206 	   an mfn.  We can tell which is which from the index. */
207 	void (*set_fixmap)(unsigned /* enum fixed_addresses */ idx,
208 			   phys_addr_t phys, pgprot_t flags);
209 #endif
210 } __no_randomize_layout;
211 
212 struct arch_spinlock;
213 #ifdef CONFIG_SMP
214 #include <asm/spinlock_types.h>
215 #endif
216 
217 struct qspinlock;
218 
219 struct pv_lock_ops {
220 	void (*queued_spin_lock_slowpath)(struct qspinlock *lock, u32 val);
221 	struct paravirt_callee_save queued_spin_unlock;
222 
223 	void (*wait)(u8 *ptr, u8 val);
224 	void (*kick)(int cpu);
225 
226 	struct paravirt_callee_save vcpu_is_preempted;
227 } __no_randomize_layout;
228 
229 /* This contains all the paravirt structures: we get a convenient
230  * number for each function using the offset which we use to indicate
231  * what to patch. */
232 struct paravirt_patch_template {
233 	struct pv_cpu_ops	cpu;
234 	struct pv_irq_ops	irq;
235 	struct pv_mmu_ops	mmu;
236 	struct pv_lock_ops	lock;
237 } __no_randomize_layout;
238 
239 extern struct pv_info pv_info;
240 extern struct paravirt_patch_template pv_ops;
241 
242 #define paravirt_ptr(op)	[paravirt_opptr] "m" (pv_ops.op)
243 
244 int paravirt_disable_iospace(void);
245 
246 /* This generates an indirect call based on the operation type number. */
247 #define PARAVIRT_CALL					\
248 	ANNOTATE_RETPOLINE_SAFE				\
249 	"call *%[paravirt_opptr];"
250 
251 /*
252  * These macros are intended to wrap calls through one of the paravirt
253  * ops structs, so that they can be later identified and patched at
254  * runtime.
255  *
256  * Normally, a call to a pv_op function is a simple indirect call:
257  * (pv_op_struct.operations)(args...).
258  *
259  * Unfortunately, this is a relatively slow operation for modern CPUs,
260  * because it cannot necessarily determine what the destination
261  * address is.  In this case, the address is a runtime constant, so at
262  * the very least we can patch the call to a simple direct call, or,
263  * ideally, patch an inline implementation into the callsite.  (Direct
264  * calls are essentially free, because the call and return addresses
265  * are completely predictable.)
266  *
267  * For i386, these macros rely on the standard gcc "regparm(3)" calling
268  * convention, in which the first three arguments are placed in %eax,
269  * %edx, %ecx (in that order), and the remaining arguments are placed
270  * on the stack.  All caller-save registers (eax,edx,ecx) are expected
271  * to be modified (either clobbered or used for return values).
272  * X86_64, on the other hand, already specifies a register-based calling
273  * conventions, returning at %rax, with parameters going in %rdi, %rsi,
274  * %rdx, and %rcx. Note that for this reason, x86_64 does not need any
275  * special handling for dealing with 4 arguments, unlike i386.
276  * However, x86_64 also has to clobber all caller saved registers, which
277  * unfortunately, are quite a bit (r8 - r11)
278  *
279  * Unfortunately there's no way to get gcc to generate the args setup
280  * for the call, and then allow the call itself to be generated by an
281  * inline asm.  Because of this, we must do the complete arg setup and
282  * return value handling from within these macros.  This is fairly
283  * cumbersome.
284  *
285  * There are 5 sets of PVOP_* macros for dealing with 0-4 arguments.
286  * It could be extended to more arguments, but there would be little
287  * to be gained from that.  For each number of arguments, there are
288  * two VCALL and CALL variants for void and non-void functions.
289  *
290  * When there is a return value, the invoker of the macro must specify
291  * the return type.  The macro then uses sizeof() on that type to
292  * determine whether it's a 32 or 64 bit value and places the return
293  * in the right register(s) (just %eax for 32-bit, and %edx:%eax for
294  * 64-bit). For x86_64 machines, it just returns in %rax regardless of
295  * the return value size.
296  *
297  * 64-bit arguments are passed as a pair of adjacent 32-bit arguments;
298  * i386 also passes 64-bit arguments as a pair of adjacent 32-bit arguments
299  * in low,high order
300  *
301  * Small structures are passed and returned in registers.  The macro
302  * calling convention can't directly deal with this, so the wrapper
303  * functions must do it.
304  *
305  * These PVOP_* macros are only defined within this header.  This
306  * means that all uses must be wrapped in inline functions.  This also
307  * makes sure the incoming and outgoing types are always correct.
308  */
309 #ifdef CONFIG_X86_32
310 #define PVOP_CALL_ARGS							\
311 	unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx;
312 
313 #define PVOP_CALL_ARG1(x)		"a" ((unsigned long)(x))
314 #define PVOP_CALL_ARG2(x)		"d" ((unsigned long)(x))
315 #define PVOP_CALL_ARG3(x)		"c" ((unsigned long)(x))
316 
317 #define PVOP_VCALL_CLOBBERS		"=a" (__eax), "=d" (__edx),	\
318 					"=c" (__ecx)
319 #define PVOP_CALL_CLOBBERS		PVOP_VCALL_CLOBBERS
320 
321 #define PVOP_VCALLEE_CLOBBERS		"=a" (__eax), "=d" (__edx)
322 #define PVOP_CALLEE_CLOBBERS		PVOP_VCALLEE_CLOBBERS
323 
324 #define EXTRA_CLOBBERS
325 #define VEXTRA_CLOBBERS
326 #else  /* CONFIG_X86_64 */
327 /* [re]ax isn't an arg, but the return val */
328 #define PVOP_CALL_ARGS						\
329 	unsigned long __edi = __edi, __esi = __esi,		\
330 		__edx = __edx, __ecx = __ecx, __eax = __eax;
331 
332 #define PVOP_CALL_ARG1(x)		"D" ((unsigned long)(x))
333 #define PVOP_CALL_ARG2(x)		"S" ((unsigned long)(x))
334 #define PVOP_CALL_ARG3(x)		"d" ((unsigned long)(x))
335 #define PVOP_CALL_ARG4(x)		"c" ((unsigned long)(x))
336 
337 #define PVOP_VCALL_CLOBBERS	"=D" (__edi),				\
338 				"=S" (__esi), "=d" (__edx),		\
339 				"=c" (__ecx)
340 #define PVOP_CALL_CLOBBERS	PVOP_VCALL_CLOBBERS, "=a" (__eax)
341 
342 /*
343  * void functions are still allowed [re]ax for scratch.
344  *
345  * The ZERO_CALL_USED REGS feature may end up zeroing out callee-saved
346  * registers. Make sure we model this with the appropriate clobbers.
347  */
348 #ifdef CONFIG_ZERO_CALL_USED_REGS
349 #define PVOP_VCALLEE_CLOBBERS	"=a" (__eax), PVOP_VCALL_CLOBBERS
350 #else
351 #define PVOP_VCALLEE_CLOBBERS	"=a" (__eax)
352 #endif
353 #define PVOP_CALLEE_CLOBBERS	PVOP_VCALLEE_CLOBBERS
354 
355 #define EXTRA_CLOBBERS	 , "r8", "r9", "r10", "r11"
356 #define VEXTRA_CLOBBERS	 , "rax", "r8", "r9", "r10", "r11"
357 #endif	/* CONFIG_X86_32 */
358 
359 #ifdef CONFIG_PARAVIRT_DEBUG
360 #define PVOP_TEST_NULL(op)	BUG_ON(pv_ops.op == NULL)
361 #else
362 #define PVOP_TEST_NULL(op)	((void)pv_ops.op)
363 #endif
364 
365 #define PVOP_RETVAL(rettype)						\
366 	({	unsigned long __mask = ~0UL;				\
367 		BUILD_BUG_ON(sizeof(rettype) > sizeof(unsigned long));	\
368 		switch (sizeof(rettype)) {				\
369 		case 1: __mask =       0xffUL; break;			\
370 		case 2: __mask =     0xffffUL; break;			\
371 		case 4: __mask = 0xffffffffUL; break;			\
372 		default: break;						\
373 		}							\
374 		__mask & __eax;						\
375 	})
376 
377 /*
378  * Use alternative patching for paravirt calls:
379  * - For replacing an indirect call with a direct one, use the "normal"
380  *   ALTERNATIVE() macro with the indirect call as the initial code sequence,
381  *   which will be replaced with the related direct call by using the
382  *   ALT_FLAG_DIRECT_CALL special case and the "always on" feature.
383  * - In case the replacement is either a direct call or a short code sequence
384  *   depending on a feature bit, the ALTERNATIVE_2() macro is being used.
385  *   The indirect call is the initial code sequence again, while the special
386  *   code sequence is selected with the specified feature bit. In case the
387  *   feature is not active, the direct call is used as above via the
388  *   ALT_FLAG_DIRECT_CALL special case and the "always on" feature.
389  */
390 #define ____PVOP_CALL(ret, op, call_clbr, extra_clbr, ...)	\
391 	({								\
392 		PVOP_CALL_ARGS;						\
393 		PVOP_TEST_NULL(op);					\
394 		asm volatile(ALTERNATIVE(PARAVIRT_CALL, ALT_CALL_INSTR,	\
395 				ALT_CALL_ALWAYS)			\
396 			     : call_clbr, ASM_CALL_CONSTRAINT		\
397 			     : paravirt_ptr(op),			\
398 			       ##__VA_ARGS__				\
399 			     : "memory", "cc" extra_clbr);		\
400 		ret;							\
401 	})
402 
403 #define ____PVOP_ALT_CALL(ret, op, alt, cond, call_clbr,		\
404 			  extra_clbr, ...)				\
405 	({								\
406 		PVOP_CALL_ARGS;						\
407 		PVOP_TEST_NULL(op);					\
408 		asm volatile(ALTERNATIVE_2(PARAVIRT_CALL,		\
409 				 ALT_CALL_INSTR, ALT_CALL_ALWAYS,	\
410 				 alt, cond)				\
411 			     : call_clbr, ASM_CALL_CONSTRAINT		\
412 			     : paravirt_ptr(op),			\
413 			       ##__VA_ARGS__				\
414 			     : "memory", "cc" extra_clbr);		\
415 		ret;							\
416 	})
417 
418 #define __PVOP_CALL(rettype, op, ...)					\
419 	____PVOP_CALL(PVOP_RETVAL(rettype), op,				\
420 		      PVOP_CALL_CLOBBERS, EXTRA_CLOBBERS, ##__VA_ARGS__)
421 
422 #define __PVOP_ALT_CALL(rettype, op, alt, cond, ...)			\
423 	____PVOP_ALT_CALL(PVOP_RETVAL(rettype), op, alt, cond,		\
424 			  PVOP_CALL_CLOBBERS, EXTRA_CLOBBERS,		\
425 			  ##__VA_ARGS__)
426 
427 #define __PVOP_CALLEESAVE(rettype, op, ...)				\
428 	____PVOP_CALL(PVOP_RETVAL(rettype), op.func,			\
429 		      PVOP_CALLEE_CLOBBERS, , ##__VA_ARGS__)
430 
431 #define __PVOP_ALT_CALLEESAVE(rettype, op, alt, cond, ...)		\
432 	____PVOP_ALT_CALL(PVOP_RETVAL(rettype), op.func, alt, cond,	\
433 			  PVOP_CALLEE_CLOBBERS, , ##__VA_ARGS__)
434 
435 
436 #define __PVOP_VCALL(op, ...)						\
437 	(void)____PVOP_CALL(, op, PVOP_VCALL_CLOBBERS,			\
438 		       VEXTRA_CLOBBERS, ##__VA_ARGS__)
439 
440 #define __PVOP_ALT_VCALL(op, alt, cond, ...)				\
441 	(void)____PVOP_ALT_CALL(, op, alt, cond,			\
442 				PVOP_VCALL_CLOBBERS, VEXTRA_CLOBBERS,	\
443 				##__VA_ARGS__)
444 
445 #define __PVOP_VCALLEESAVE(op, ...)					\
446 	(void)____PVOP_CALL(, op.func,					\
447 			    PVOP_VCALLEE_CLOBBERS, , ##__VA_ARGS__)
448 
449 #define __PVOP_ALT_VCALLEESAVE(op, alt, cond, ...)			\
450 	(void)____PVOP_ALT_CALL(, op.func, alt, cond,			\
451 				PVOP_VCALLEE_CLOBBERS, , ##__VA_ARGS__)
452 
453 
454 #define PVOP_CALL0(rettype, op)						\
455 	__PVOP_CALL(rettype, op)
456 #define PVOP_VCALL0(op)							\
457 	__PVOP_VCALL(op)
458 #define PVOP_ALT_CALL0(rettype, op, alt, cond)				\
459 	__PVOP_ALT_CALL(rettype, op, alt, cond)
460 #define PVOP_ALT_VCALL0(op, alt, cond)					\
461 	__PVOP_ALT_VCALL(op, alt, cond)
462 
463 #define PVOP_CALLEE0(rettype, op)					\
464 	__PVOP_CALLEESAVE(rettype, op)
465 #define PVOP_VCALLEE0(op)						\
466 	__PVOP_VCALLEESAVE(op)
467 #define PVOP_ALT_CALLEE0(rettype, op, alt, cond)			\
468 	__PVOP_ALT_CALLEESAVE(rettype, op, alt, cond)
469 #define PVOP_ALT_VCALLEE0(op, alt, cond)				\
470 	__PVOP_ALT_VCALLEESAVE(op, alt, cond)
471 
472 
473 #define PVOP_CALL1(rettype, op, arg1)					\
474 	__PVOP_CALL(rettype, op, PVOP_CALL_ARG1(arg1))
475 #define PVOP_VCALL1(op, arg1)						\
476 	__PVOP_VCALL(op, PVOP_CALL_ARG1(arg1))
477 #define PVOP_ALT_VCALL1(op, arg1, alt, cond)				\
478 	__PVOP_ALT_VCALL(op, alt, cond, PVOP_CALL_ARG1(arg1))
479 
480 #define PVOP_CALLEE1(rettype, op, arg1)					\
481 	__PVOP_CALLEESAVE(rettype, op, PVOP_CALL_ARG1(arg1))
482 #define PVOP_VCALLEE1(op, arg1)						\
483 	__PVOP_VCALLEESAVE(op, PVOP_CALL_ARG1(arg1))
484 #define PVOP_ALT_CALLEE1(rettype, op, arg1, alt, cond)			\
485 	__PVOP_ALT_CALLEESAVE(rettype, op, alt, cond, PVOP_CALL_ARG1(arg1))
486 #define PVOP_ALT_VCALLEE1(op, arg1, alt, cond)				\
487 	__PVOP_ALT_VCALLEESAVE(op, alt, cond, PVOP_CALL_ARG1(arg1))
488 
489 
490 #define PVOP_CALL2(rettype, op, arg1, arg2)				\
491 	__PVOP_CALL(rettype, op, PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2))
492 #define PVOP_VCALL2(op, arg1, arg2)					\
493 	__PVOP_VCALL(op, PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2))
494 
495 #define PVOP_CALL3(rettype, op, arg1, arg2, arg3)			\
496 	__PVOP_CALL(rettype, op, PVOP_CALL_ARG1(arg1),			\
497 		    PVOP_CALL_ARG2(arg2), PVOP_CALL_ARG3(arg3))
498 #define PVOP_VCALL3(op, arg1, arg2, arg3)				\
499 	__PVOP_VCALL(op, PVOP_CALL_ARG1(arg1),				\
500 		     PVOP_CALL_ARG2(arg2), PVOP_CALL_ARG3(arg3))
501 
502 #define PVOP_CALL4(rettype, op, arg1, arg2, arg3, arg4)			\
503 	__PVOP_CALL(rettype, op,					\
504 		    PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2),		\
505 		    PVOP_CALL_ARG3(arg3), PVOP_CALL_ARG4(arg4))
506 #define PVOP_VCALL4(op, arg1, arg2, arg3, arg4)				\
507 	__PVOP_VCALL(op, PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2),	\
508 		     PVOP_CALL_ARG3(arg3), PVOP_CALL_ARG4(arg4))
509 
510 unsigned long paravirt_ret0(void);
511 #ifdef CONFIG_PARAVIRT_XXL
512 u64 _paravirt_ident_64(u64);
513 unsigned long pv_native_save_fl(void);
514 void pv_native_irq_disable(void);
515 void pv_native_irq_enable(void);
516 unsigned long pv_native_read_cr2(void);
517 #endif
518 
519 #define paravirt_nop	((void *)nop_func)
520 
521 #endif	/* __ASSEMBLY__ */
522 
523 #define ALT_NOT_XEN	ALT_NOT(X86_FEATURE_XENPV)
524 
525 #endif  /* CONFIG_PARAVIRT */
526 #endif	/* _ASM_X86_PARAVIRT_TYPES_H */
527