xref: /linux/arch/x86/include/asm/xen/hypercall.h (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /******************************************************************************
2  * hypercall.h
3  *
4  * Linux-specific hypervisor handling.
5  *
6  * Copyright (c) 2002-2004, K A Fraser
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License version 2
10  * as published by the Free Software Foundation; or, when distributed
11  * separately from the Linux kernel or incorporated into other
12  * software packages, subject to the following license:
13  *
14  * Permission is hereby granted, free of charge, to any person obtaining a copy
15  * of this source file (the "Software"), to deal in the Software without
16  * restriction, including without limitation the rights to use, copy, modify,
17  * merge, publish, distribute, sublicense, and/or sell copies of the Software,
18  * and to permit persons to whom the Software is furnished to do so, subject to
19  * the following conditions:
20  *
21  * The above copyright notice and this permission notice shall be included in
22  * all copies or substantial portions of the Software.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
25  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
26  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
27  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
28  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
29  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
30  * IN THE SOFTWARE.
31  */
32 
33 #ifndef _ASM_X86_XEN_HYPERCALL_H
34 #define _ASM_X86_XEN_HYPERCALL_H
35 
36 #include <linux/kernel.h>
37 #include <linux/spinlock.h>
38 #include <linux/errno.h>
39 #include <linux/string.h>
40 #include <linux/types.h>
41 
42 #include <trace/events/xen.h>
43 
44 #include <asm/page.h>
45 #include <asm/pgtable.h>
46 
47 #include <xen/interface/xen.h>
48 #include <xen/interface/sched.h>
49 #include <xen/interface/physdev.h>
50 #include <xen/interface/platform.h>
51 #include <xen/interface/xen-mca.h>
52 
53 /*
54  * The hypercall asms have to meet several constraints:
55  * - Work on 32- and 64-bit.
56  *    The two architectures put their arguments in different sets of
57  *    registers.
58  *
59  * - Work around asm syntax quirks
60  *    It isn't possible to specify one of the rNN registers in a
61  *    constraint, so we use explicit register variables to get the
62  *    args into the right place.
63  *
64  * - Mark all registers as potentially clobbered
65  *    Even unused parameters can be clobbered by the hypervisor, so we
66  *    need to make sure gcc knows it.
67  *
68  * - Avoid compiler bugs.
69  *    This is the tricky part.  Because x86_32 has such a constrained
70  *    register set, gcc versions below 4.3 have trouble generating
71  *    code when all the arg registers and memory are trashed by the
72  *    asm.  There are syntactically simpler ways of achieving the
73  *    semantics below, but they cause the compiler to crash.
74  *
75  *    The only combination I found which works is:
76  *     - assign the __argX variables first
77  *     - list all actually used parameters as "+r" (__argX)
78  *     - clobber the rest
79  *
80  * The result certainly isn't pretty, and it really shows up cpp's
81  * weakness as as macro language.  Sorry.  (But let's just give thanks
82  * there aren't more than 5 arguments...)
83  */
84 
85 extern struct { char _entry[32]; } hypercall_page[];
86 
87 #define __HYPERCALL		"call hypercall_page+%c[offset]"
88 #define __HYPERCALL_ENTRY(x)						\
89 	[offset] "i" (__HYPERVISOR_##x * sizeof(hypercall_page[0]))
90 
91 #ifdef CONFIG_X86_32
92 #define __HYPERCALL_RETREG	"eax"
93 #define __HYPERCALL_ARG1REG	"ebx"
94 #define __HYPERCALL_ARG2REG	"ecx"
95 #define __HYPERCALL_ARG3REG	"edx"
96 #define __HYPERCALL_ARG4REG	"esi"
97 #define __HYPERCALL_ARG5REG	"edi"
98 #else
99 #define __HYPERCALL_RETREG	"rax"
100 #define __HYPERCALL_ARG1REG	"rdi"
101 #define __HYPERCALL_ARG2REG	"rsi"
102 #define __HYPERCALL_ARG3REG	"rdx"
103 #define __HYPERCALL_ARG4REG	"r10"
104 #define __HYPERCALL_ARG5REG	"r8"
105 #endif
106 
107 #define __HYPERCALL_DECLS						\
108 	register unsigned long __res  asm(__HYPERCALL_RETREG);		\
109 	register unsigned long __arg1 asm(__HYPERCALL_ARG1REG) = __arg1; \
110 	register unsigned long __arg2 asm(__HYPERCALL_ARG2REG) = __arg2; \
111 	register unsigned long __arg3 asm(__HYPERCALL_ARG3REG) = __arg3; \
112 	register unsigned long __arg4 asm(__HYPERCALL_ARG4REG) = __arg4; \
113 	register unsigned long __arg5 asm(__HYPERCALL_ARG5REG) = __arg5; \
114 	register void *__sp asm(_ASM_SP);
115 
116 #define __HYPERCALL_0PARAM	"=r" (__res), "+r" (__sp)
117 #define __HYPERCALL_1PARAM	__HYPERCALL_0PARAM, "+r" (__arg1)
118 #define __HYPERCALL_2PARAM	__HYPERCALL_1PARAM, "+r" (__arg2)
119 #define __HYPERCALL_3PARAM	__HYPERCALL_2PARAM, "+r" (__arg3)
120 #define __HYPERCALL_4PARAM	__HYPERCALL_3PARAM, "+r" (__arg4)
121 #define __HYPERCALL_5PARAM	__HYPERCALL_4PARAM, "+r" (__arg5)
122 
123 #define __HYPERCALL_0ARG()
124 #define __HYPERCALL_1ARG(a1)						\
125 	__HYPERCALL_0ARG()		__arg1 = (unsigned long)(a1);
126 #define __HYPERCALL_2ARG(a1,a2)						\
127 	__HYPERCALL_1ARG(a1)		__arg2 = (unsigned long)(a2);
128 #define __HYPERCALL_3ARG(a1,a2,a3)					\
129 	__HYPERCALL_2ARG(a1,a2)		__arg3 = (unsigned long)(a3);
130 #define __HYPERCALL_4ARG(a1,a2,a3,a4)					\
131 	__HYPERCALL_3ARG(a1,a2,a3)	__arg4 = (unsigned long)(a4);
132 #define __HYPERCALL_5ARG(a1,a2,a3,a4,a5)				\
133 	__HYPERCALL_4ARG(a1,a2,a3,a4)	__arg5 = (unsigned long)(a5);
134 
135 #define __HYPERCALL_CLOBBER5	"memory"
136 #define __HYPERCALL_CLOBBER4	__HYPERCALL_CLOBBER5, __HYPERCALL_ARG5REG
137 #define __HYPERCALL_CLOBBER3	__HYPERCALL_CLOBBER4, __HYPERCALL_ARG4REG
138 #define __HYPERCALL_CLOBBER2	__HYPERCALL_CLOBBER3, __HYPERCALL_ARG3REG
139 #define __HYPERCALL_CLOBBER1	__HYPERCALL_CLOBBER2, __HYPERCALL_ARG2REG
140 #define __HYPERCALL_CLOBBER0	__HYPERCALL_CLOBBER1, __HYPERCALL_ARG1REG
141 
142 #define _hypercall0(type, name)						\
143 ({									\
144 	__HYPERCALL_DECLS;						\
145 	__HYPERCALL_0ARG();						\
146 	asm volatile (__HYPERCALL					\
147 		      : __HYPERCALL_0PARAM				\
148 		      : __HYPERCALL_ENTRY(name)				\
149 		      : __HYPERCALL_CLOBBER0);				\
150 	(type)__res;							\
151 })
152 
153 #define _hypercall1(type, name, a1)					\
154 ({									\
155 	__HYPERCALL_DECLS;						\
156 	__HYPERCALL_1ARG(a1);						\
157 	asm volatile (__HYPERCALL					\
158 		      : __HYPERCALL_1PARAM				\
159 		      : __HYPERCALL_ENTRY(name)				\
160 		      : __HYPERCALL_CLOBBER1);				\
161 	(type)__res;							\
162 })
163 
164 #define _hypercall2(type, name, a1, a2)					\
165 ({									\
166 	__HYPERCALL_DECLS;						\
167 	__HYPERCALL_2ARG(a1, a2);					\
168 	asm volatile (__HYPERCALL					\
169 		      : __HYPERCALL_2PARAM				\
170 		      : __HYPERCALL_ENTRY(name)				\
171 		      : __HYPERCALL_CLOBBER2);				\
172 	(type)__res;							\
173 })
174 
175 #define _hypercall3(type, name, a1, a2, a3)				\
176 ({									\
177 	__HYPERCALL_DECLS;						\
178 	__HYPERCALL_3ARG(a1, a2, a3);					\
179 	asm volatile (__HYPERCALL					\
180 		      : __HYPERCALL_3PARAM				\
181 		      : __HYPERCALL_ENTRY(name)				\
182 		      : __HYPERCALL_CLOBBER3);				\
183 	(type)__res;							\
184 })
185 
186 #define _hypercall4(type, name, a1, a2, a3, a4)				\
187 ({									\
188 	__HYPERCALL_DECLS;						\
189 	__HYPERCALL_4ARG(a1, a2, a3, a4);				\
190 	asm volatile (__HYPERCALL					\
191 		      : __HYPERCALL_4PARAM				\
192 		      : __HYPERCALL_ENTRY(name)				\
193 		      : __HYPERCALL_CLOBBER4);				\
194 	(type)__res;							\
195 })
196 
197 #define _hypercall5(type, name, a1, a2, a3, a4, a5)			\
198 ({									\
199 	__HYPERCALL_DECLS;						\
200 	__HYPERCALL_5ARG(a1, a2, a3, a4, a5);				\
201 	asm volatile (__HYPERCALL					\
202 		      : __HYPERCALL_5PARAM				\
203 		      : __HYPERCALL_ENTRY(name)				\
204 		      : __HYPERCALL_CLOBBER5);				\
205 	(type)__res;							\
206 })
207 
208 static inline long
209 privcmd_call(unsigned call,
210 	     unsigned long a1, unsigned long a2,
211 	     unsigned long a3, unsigned long a4,
212 	     unsigned long a5)
213 {
214 	__HYPERCALL_DECLS;
215 	__HYPERCALL_5ARG(a1, a2, a3, a4, a5);
216 
217 	asm volatile("call *%[call]"
218 		     : __HYPERCALL_5PARAM
219 		     : [call] "a" (&hypercall_page[call])
220 		     : __HYPERCALL_CLOBBER5);
221 
222 	return (long)__res;
223 }
224 
225 static inline int
226 HYPERVISOR_set_trap_table(struct trap_info *table)
227 {
228 	return _hypercall1(int, set_trap_table, table);
229 }
230 
231 static inline int
232 HYPERVISOR_mmu_update(struct mmu_update *req, int count,
233 		      int *success_count, domid_t domid)
234 {
235 	return _hypercall4(int, mmu_update, req, count, success_count, domid);
236 }
237 
238 static inline int
239 HYPERVISOR_mmuext_op(struct mmuext_op *op, int count,
240 		     int *success_count, domid_t domid)
241 {
242 	return _hypercall4(int, mmuext_op, op, count, success_count, domid);
243 }
244 
245 static inline int
246 HYPERVISOR_set_gdt(unsigned long *frame_list, int entries)
247 {
248 	return _hypercall2(int, set_gdt, frame_list, entries);
249 }
250 
251 static inline int
252 HYPERVISOR_stack_switch(unsigned long ss, unsigned long esp)
253 {
254 	return _hypercall2(int, stack_switch, ss, esp);
255 }
256 
257 #ifdef CONFIG_X86_32
258 static inline int
259 HYPERVISOR_set_callbacks(unsigned long event_selector,
260 			 unsigned long event_address,
261 			 unsigned long failsafe_selector,
262 			 unsigned long failsafe_address)
263 {
264 	return _hypercall4(int, set_callbacks,
265 			   event_selector, event_address,
266 			   failsafe_selector, failsafe_address);
267 }
268 #else  /* CONFIG_X86_64 */
269 static inline int
270 HYPERVISOR_set_callbacks(unsigned long event_address,
271 			unsigned long failsafe_address,
272 			unsigned long syscall_address)
273 {
274 	return _hypercall3(int, set_callbacks,
275 			   event_address, failsafe_address,
276 			   syscall_address);
277 }
278 #endif  /* CONFIG_X86_{32,64} */
279 
280 static inline int
281 HYPERVISOR_callback_op(int cmd, void *arg)
282 {
283 	return _hypercall2(int, callback_op, cmd, arg);
284 }
285 
286 static inline int
287 HYPERVISOR_fpu_taskswitch(int set)
288 {
289 	return _hypercall1(int, fpu_taskswitch, set);
290 }
291 
292 static inline int
293 HYPERVISOR_sched_op(int cmd, void *arg)
294 {
295 	return _hypercall2(int, sched_op, cmd, arg);
296 }
297 
298 static inline long
299 HYPERVISOR_set_timer_op(u64 timeout)
300 {
301 	unsigned long timeout_hi = (unsigned long)(timeout>>32);
302 	unsigned long timeout_lo = (unsigned long)timeout;
303 	return _hypercall2(long, set_timer_op, timeout_lo, timeout_hi);
304 }
305 
306 static inline int
307 HYPERVISOR_mca(struct xen_mc *mc_op)
308 {
309 	mc_op->interface_version = XEN_MCA_INTERFACE_VERSION;
310 	return _hypercall1(int, mca, mc_op);
311 }
312 
313 static inline int
314 HYPERVISOR_platform_op(struct xen_platform_op *op)
315 {
316 	op->interface_version = XENPF_INTERFACE_VERSION;
317 	return _hypercall1(int, platform_op, op);
318 }
319 
320 static inline int
321 HYPERVISOR_set_debugreg(int reg, unsigned long value)
322 {
323 	return _hypercall2(int, set_debugreg, reg, value);
324 }
325 
326 static inline unsigned long
327 HYPERVISOR_get_debugreg(int reg)
328 {
329 	return _hypercall1(unsigned long, get_debugreg, reg);
330 }
331 
332 static inline int
333 HYPERVISOR_update_descriptor(u64 ma, u64 desc)
334 {
335 	if (sizeof(u64) == sizeof(long))
336 		return _hypercall2(int, update_descriptor, ma, desc);
337 	return _hypercall4(int, update_descriptor, ma, ma>>32, desc, desc>>32);
338 }
339 
340 static inline long
341 HYPERVISOR_memory_op(unsigned int cmd, void *arg)
342 {
343 	return _hypercall2(long, memory_op, cmd, arg);
344 }
345 
346 static inline int
347 HYPERVISOR_multicall(void *call_list, uint32_t nr_calls)
348 {
349 	return _hypercall2(int, multicall, call_list, nr_calls);
350 }
351 
352 static inline int
353 HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val,
354 			     unsigned long flags)
355 {
356 	if (sizeof(new_val) == sizeof(long))
357 		return _hypercall3(int, update_va_mapping, va,
358 				   new_val.pte, flags);
359 	else
360 		return _hypercall4(int, update_va_mapping, va,
361 				   new_val.pte, new_val.pte >> 32, flags);
362 }
363 extern int __must_check xen_event_channel_op_compat(int, void *);
364 
365 static inline int
366 HYPERVISOR_event_channel_op(int cmd, void *arg)
367 {
368 	int rc = _hypercall2(int, event_channel_op, cmd, arg);
369 	if (unlikely(rc == -ENOSYS))
370 		rc = xen_event_channel_op_compat(cmd, arg);
371 	return rc;
372 }
373 
374 static inline int
375 HYPERVISOR_xen_version(int cmd, void *arg)
376 {
377 	return _hypercall2(int, xen_version, cmd, arg);
378 }
379 
380 static inline int
381 HYPERVISOR_console_io(int cmd, int count, char *str)
382 {
383 	return _hypercall3(int, console_io, cmd, count, str);
384 }
385 
386 extern int __must_check xen_physdev_op_compat(int, void *);
387 
388 static inline int
389 HYPERVISOR_physdev_op(int cmd, void *arg)
390 {
391 	int rc = _hypercall2(int, physdev_op, cmd, arg);
392 	if (unlikely(rc == -ENOSYS))
393 		rc = xen_physdev_op_compat(cmd, arg);
394 	return rc;
395 }
396 
397 static inline int
398 HYPERVISOR_grant_table_op(unsigned int cmd, void *uop, unsigned int count)
399 {
400 	return _hypercall3(int, grant_table_op, cmd, uop, count);
401 }
402 
403 static inline int
404 HYPERVISOR_update_va_mapping_otherdomain(unsigned long va, pte_t new_val,
405 					 unsigned long flags, domid_t domid)
406 {
407 	if (sizeof(new_val) == sizeof(long))
408 		return _hypercall4(int, update_va_mapping_otherdomain, va,
409 				   new_val.pte, flags, domid);
410 	else
411 		return _hypercall5(int, update_va_mapping_otherdomain, va,
412 				   new_val.pte, new_val.pte >> 32,
413 				   flags, domid);
414 }
415 
416 static inline int
417 HYPERVISOR_vm_assist(unsigned int cmd, unsigned int type)
418 {
419 	return _hypercall2(int, vm_assist, cmd, type);
420 }
421 
422 static inline int
423 HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args)
424 {
425 	return _hypercall3(int, vcpu_op, cmd, vcpuid, extra_args);
426 }
427 
428 #ifdef CONFIG_X86_64
429 static inline int
430 HYPERVISOR_set_segment_base(int reg, unsigned long value)
431 {
432 	return _hypercall2(int, set_segment_base, reg, value);
433 }
434 #endif
435 
436 static inline int
437 HYPERVISOR_suspend(unsigned long start_info_mfn)
438 {
439 	struct sched_shutdown r = { .reason = SHUTDOWN_suspend };
440 
441 	/*
442 	 * For a PV guest the tools require that the start_info mfn be
443 	 * present in rdx/edx when the hypercall is made. Per the
444 	 * hypercall calling convention this is the third hypercall
445 	 * argument, which is start_info_mfn here.
446 	 */
447 	return _hypercall3(int, sched_op, SCHEDOP_shutdown, &r, start_info_mfn);
448 }
449 
450 static inline int
451 HYPERVISOR_nmi_op(unsigned long op, unsigned long arg)
452 {
453 	return _hypercall2(int, nmi_op, op, arg);
454 }
455 
456 static inline unsigned long __must_check
457 HYPERVISOR_hvm_op(int op, void *arg)
458 {
459        return _hypercall2(unsigned long, hvm_op, op, arg);
460 }
461 
462 static inline int
463 HYPERVISOR_tmem_op(
464 	struct tmem_op *op)
465 {
466 	return _hypercall1(int, tmem_op, op);
467 }
468 
469 static inline int
470 HYPERVISOR_xenpmu_op(unsigned int op, void *arg)
471 {
472 	return _hypercall2(int, xenpmu_op, op, arg);
473 }
474 
475 static inline int
476 HYPERVISOR_dm_op(
477 	domid_t dom, unsigned int nr_bufs, void *bufs)
478 {
479 	return _hypercall3(int, dm_op, dom, nr_bufs, bufs);
480 }
481 
482 static inline void
483 MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set)
484 {
485 	mcl->op = __HYPERVISOR_fpu_taskswitch;
486 	mcl->args[0] = set;
487 
488 	trace_xen_mc_entry(mcl, 1);
489 }
490 
491 static inline void
492 MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va,
493 			pte_t new_val, unsigned long flags)
494 {
495 	mcl->op = __HYPERVISOR_update_va_mapping;
496 	mcl->args[0] = va;
497 	if (sizeof(new_val) == sizeof(long)) {
498 		mcl->args[1] = new_val.pte;
499 		mcl->args[2] = flags;
500 	} else {
501 		mcl->args[1] = new_val.pte;
502 		mcl->args[2] = new_val.pte >> 32;
503 		mcl->args[3] = flags;
504 	}
505 
506 	trace_xen_mc_entry(mcl, sizeof(new_val) == sizeof(long) ? 3 : 4);
507 }
508 
509 static inline void
510 MULTI_grant_table_op(struct multicall_entry *mcl, unsigned int cmd,
511 		     void *uop, unsigned int count)
512 {
513 	mcl->op = __HYPERVISOR_grant_table_op;
514 	mcl->args[0] = cmd;
515 	mcl->args[1] = (unsigned long)uop;
516 	mcl->args[2] = count;
517 
518 	trace_xen_mc_entry(mcl, 3);
519 }
520 
521 static inline void
522 MULTI_update_va_mapping_otherdomain(struct multicall_entry *mcl, unsigned long va,
523 				    pte_t new_val, unsigned long flags,
524 				    domid_t domid)
525 {
526 	mcl->op = __HYPERVISOR_update_va_mapping_otherdomain;
527 	mcl->args[0] = va;
528 	if (sizeof(new_val) == sizeof(long)) {
529 		mcl->args[1] = new_val.pte;
530 		mcl->args[2] = flags;
531 		mcl->args[3] = domid;
532 	} else {
533 		mcl->args[1] = new_val.pte;
534 		mcl->args[2] = new_val.pte >> 32;
535 		mcl->args[3] = flags;
536 		mcl->args[4] = domid;
537 	}
538 
539 	trace_xen_mc_entry(mcl, sizeof(new_val) == sizeof(long) ? 4 : 5);
540 }
541 
542 static inline void
543 MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr,
544 			struct desc_struct desc)
545 {
546 	mcl->op = __HYPERVISOR_update_descriptor;
547 	if (sizeof(maddr) == sizeof(long)) {
548 		mcl->args[0] = maddr;
549 		mcl->args[1] = *(unsigned long *)&desc;
550 	} else {
551 		mcl->args[0] = maddr;
552 		mcl->args[1] = maddr >> 32;
553 		mcl->args[2] = desc.a;
554 		mcl->args[3] = desc.b;
555 	}
556 
557 	trace_xen_mc_entry(mcl, sizeof(maddr) == sizeof(long) ? 2 : 4);
558 }
559 
560 static inline void
561 MULTI_memory_op(struct multicall_entry *mcl, unsigned int cmd, void *arg)
562 {
563 	mcl->op = __HYPERVISOR_memory_op;
564 	mcl->args[0] = cmd;
565 	mcl->args[1] = (unsigned long)arg;
566 
567 	trace_xen_mc_entry(mcl, 2);
568 }
569 
570 static inline void
571 MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req,
572 		 int count, int *success_count, domid_t domid)
573 {
574 	mcl->op = __HYPERVISOR_mmu_update;
575 	mcl->args[0] = (unsigned long)req;
576 	mcl->args[1] = count;
577 	mcl->args[2] = (unsigned long)success_count;
578 	mcl->args[3] = domid;
579 
580 	trace_xen_mc_entry(mcl, 4);
581 }
582 
583 static inline void
584 MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count,
585 		int *success_count, domid_t domid)
586 {
587 	mcl->op = __HYPERVISOR_mmuext_op;
588 	mcl->args[0] = (unsigned long)op;
589 	mcl->args[1] = count;
590 	mcl->args[2] = (unsigned long)success_count;
591 	mcl->args[3] = domid;
592 
593 	trace_xen_mc_entry(mcl, 4);
594 }
595 
596 static inline void
597 MULTI_set_gdt(struct multicall_entry *mcl, unsigned long *frames, int entries)
598 {
599 	mcl->op = __HYPERVISOR_set_gdt;
600 	mcl->args[0] = (unsigned long)frames;
601 	mcl->args[1] = entries;
602 
603 	trace_xen_mc_entry(mcl, 2);
604 }
605 
606 static inline void
607 MULTI_stack_switch(struct multicall_entry *mcl,
608 		   unsigned long ss, unsigned long esp)
609 {
610 	mcl->op = __HYPERVISOR_stack_switch;
611 	mcl->args[0] = ss;
612 	mcl->args[1] = esp;
613 
614 	trace_xen_mc_entry(mcl, 2);
615 }
616 
617 #endif /* _ASM_X86_XEN_HYPERCALL_H */
618