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
85extern 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
115#define __HYPERCALL_0PARAM	"=r" (__res)
116#define __HYPERCALL_1PARAM	__HYPERCALL_0PARAM, "+r" (__arg1)
117#define __HYPERCALL_2PARAM	__HYPERCALL_1PARAM, "+r" (__arg2)
118#define __HYPERCALL_3PARAM	__HYPERCALL_2PARAM, "+r" (__arg3)
119#define __HYPERCALL_4PARAM	__HYPERCALL_3PARAM, "+r" (__arg4)
120#define __HYPERCALL_5PARAM	__HYPERCALL_4PARAM, "+r" (__arg5)
121
122#define __HYPERCALL_0ARG()
123#define __HYPERCALL_1ARG(a1)						\
124	__HYPERCALL_0ARG()		__arg1 = (unsigned long)(a1);
125#define __HYPERCALL_2ARG(a1,a2)						\
126	__HYPERCALL_1ARG(a1)		__arg2 = (unsigned long)(a2);
127#define __HYPERCALL_3ARG(a1,a2,a3)					\
128	__HYPERCALL_2ARG(a1,a2)		__arg3 = (unsigned long)(a3);
129#define __HYPERCALL_4ARG(a1,a2,a3,a4)					\
130	__HYPERCALL_3ARG(a1,a2,a3)	__arg4 = (unsigned long)(a4);
131#define __HYPERCALL_5ARG(a1,a2,a3,a4,a5)				\
132	__HYPERCALL_4ARG(a1,a2,a3,a4)	__arg5 = (unsigned long)(a5);
133
134#define __HYPERCALL_CLOBBER5	"memory"
135#define __HYPERCALL_CLOBBER4	__HYPERCALL_CLOBBER5, __HYPERCALL_ARG5REG
136#define __HYPERCALL_CLOBBER3	__HYPERCALL_CLOBBER4, __HYPERCALL_ARG4REG
137#define __HYPERCALL_CLOBBER2	__HYPERCALL_CLOBBER3, __HYPERCALL_ARG3REG
138#define __HYPERCALL_CLOBBER1	__HYPERCALL_CLOBBER2, __HYPERCALL_ARG2REG
139#define __HYPERCALL_CLOBBER0	__HYPERCALL_CLOBBER1, __HYPERCALL_ARG1REG
140
141#define _hypercall0(type, name)						\
142({									\
143	__HYPERCALL_DECLS;						\
144	__HYPERCALL_0ARG();						\
145	asm volatile (__HYPERCALL					\
146		      : __HYPERCALL_0PARAM				\
147		      : __HYPERCALL_ENTRY(name)				\
148		      : __HYPERCALL_CLOBBER0);				\
149	(type)__res;							\
150})
151
152#define _hypercall1(type, name, a1)					\
153({									\
154	__HYPERCALL_DECLS;						\
155	__HYPERCALL_1ARG(a1);						\
156	asm volatile (__HYPERCALL					\
157		      : __HYPERCALL_1PARAM				\
158		      : __HYPERCALL_ENTRY(name)				\
159		      : __HYPERCALL_CLOBBER1);				\
160	(type)__res;							\
161})
162
163#define _hypercall2(type, name, a1, a2)					\
164({									\
165	__HYPERCALL_DECLS;						\
166	__HYPERCALL_2ARG(a1, a2);					\
167	asm volatile (__HYPERCALL					\
168		      : __HYPERCALL_2PARAM				\
169		      : __HYPERCALL_ENTRY(name)				\
170		      : __HYPERCALL_CLOBBER2);				\
171	(type)__res;							\
172})
173
174#define _hypercall3(type, name, a1, a2, a3)				\
175({									\
176	__HYPERCALL_DECLS;						\
177	__HYPERCALL_3ARG(a1, a2, a3);					\
178	asm volatile (__HYPERCALL					\
179		      : __HYPERCALL_3PARAM				\
180		      : __HYPERCALL_ENTRY(name)				\
181		      : __HYPERCALL_CLOBBER3);				\
182	(type)__res;							\
183})
184
185#define _hypercall4(type, name, a1, a2, a3, a4)				\
186({									\
187	__HYPERCALL_DECLS;						\
188	__HYPERCALL_4ARG(a1, a2, a3, a4);				\
189	asm volatile (__HYPERCALL					\
190		      : __HYPERCALL_4PARAM				\
191		      : __HYPERCALL_ENTRY(name)				\
192		      : __HYPERCALL_CLOBBER4);				\
193	(type)__res;							\
194})
195
196#define _hypercall5(type, name, a1, a2, a3, a4, a5)			\
197({									\
198	__HYPERCALL_DECLS;						\
199	__HYPERCALL_5ARG(a1, a2, a3, a4, a5);				\
200	asm volatile (__HYPERCALL					\
201		      : __HYPERCALL_5PARAM				\
202		      : __HYPERCALL_ENTRY(name)				\
203		      : __HYPERCALL_CLOBBER5);				\
204	(type)__res;							\
205})
206
207static inline long
208privcmd_call(unsigned call,
209	     unsigned long a1, unsigned long a2,
210	     unsigned long a3, unsigned long a4,
211	     unsigned long a5)
212{
213	__HYPERCALL_DECLS;
214	__HYPERCALL_5ARG(a1, a2, a3, a4, a5);
215
216	asm volatile("call *%[call]"
217		     : __HYPERCALL_5PARAM
218		     : [call] "a" (&hypercall_page[call])
219		     : __HYPERCALL_CLOBBER5);
220
221	return (long)__res;
222}
223
224static inline int
225HYPERVISOR_set_trap_table(struct trap_info *table)
226{
227	return _hypercall1(int, set_trap_table, table);
228}
229
230static inline int
231HYPERVISOR_mmu_update(struct mmu_update *req, int count,
232		      int *success_count, domid_t domid)
233{
234	return _hypercall4(int, mmu_update, req, count, success_count, domid);
235}
236
237static inline int
238HYPERVISOR_mmuext_op(struct mmuext_op *op, int count,
239		     int *success_count, domid_t domid)
240{
241	return _hypercall4(int, mmuext_op, op, count, success_count, domid);
242}
243
244static inline int
245HYPERVISOR_set_gdt(unsigned long *frame_list, int entries)
246{
247	return _hypercall2(int, set_gdt, frame_list, entries);
248}
249
250static inline int
251HYPERVISOR_stack_switch(unsigned long ss, unsigned long esp)
252{
253	return _hypercall2(int, stack_switch, ss, esp);
254}
255
256#ifdef CONFIG_X86_32
257static inline int
258HYPERVISOR_set_callbacks(unsigned long event_selector,
259			 unsigned long event_address,
260			 unsigned long failsafe_selector,
261			 unsigned long failsafe_address)
262{
263	return _hypercall4(int, set_callbacks,
264			   event_selector, event_address,
265			   failsafe_selector, failsafe_address);
266}
267#else  /* CONFIG_X86_64 */
268static inline int
269HYPERVISOR_set_callbacks(unsigned long event_address,
270			unsigned long failsafe_address,
271			unsigned long syscall_address)
272{
273	return _hypercall3(int, set_callbacks,
274			   event_address, failsafe_address,
275			   syscall_address);
276}
277#endif  /* CONFIG_X86_{32,64} */
278
279static inline int
280HYPERVISOR_callback_op(int cmd, void *arg)
281{
282	return _hypercall2(int, callback_op, cmd, arg);
283}
284
285static inline int
286HYPERVISOR_fpu_taskswitch(int set)
287{
288	return _hypercall1(int, fpu_taskswitch, set);
289}
290
291static inline int
292HYPERVISOR_sched_op(int cmd, void *arg)
293{
294	return _hypercall2(int, sched_op, cmd, arg);
295}
296
297static inline long
298HYPERVISOR_set_timer_op(u64 timeout)
299{
300	unsigned long timeout_hi = (unsigned long)(timeout>>32);
301	unsigned long timeout_lo = (unsigned long)timeout;
302	return _hypercall2(long, set_timer_op, timeout_lo, timeout_hi);
303}
304
305static inline int
306HYPERVISOR_mca(struct xen_mc *mc_op)
307{
308	mc_op->interface_version = XEN_MCA_INTERFACE_VERSION;
309	return _hypercall1(int, mca, mc_op);
310}
311
312static inline int
313HYPERVISOR_dom0_op(struct xen_platform_op *platform_op)
314{
315	platform_op->interface_version = XENPF_INTERFACE_VERSION;
316	return _hypercall1(int, dom0_op, platform_op);
317}
318
319static inline int
320HYPERVISOR_set_debugreg(int reg, unsigned long value)
321{
322	return _hypercall2(int, set_debugreg, reg, value);
323}
324
325static inline unsigned long
326HYPERVISOR_get_debugreg(int reg)
327{
328	return _hypercall1(unsigned long, get_debugreg, reg);
329}
330
331static inline int
332HYPERVISOR_update_descriptor(u64 ma, u64 desc)
333{
334	if (sizeof(u64) == sizeof(long))
335		return _hypercall2(int, update_descriptor, ma, desc);
336	return _hypercall4(int, update_descriptor, ma, ma>>32, desc, desc>>32);
337}
338
339static inline int
340HYPERVISOR_memory_op(unsigned int cmd, void *arg)
341{
342	return _hypercall2(int, memory_op, cmd, arg);
343}
344
345static inline int
346HYPERVISOR_multicall(void *call_list, uint32_t nr_calls)
347{
348	return _hypercall2(int, multicall, call_list, nr_calls);
349}
350
351static inline int
352HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val,
353			     unsigned long flags)
354{
355	if (sizeof(new_val) == sizeof(long))
356		return _hypercall3(int, update_va_mapping, va,
357				   new_val.pte, flags);
358	else
359		return _hypercall4(int, update_va_mapping, va,
360				   new_val.pte, new_val.pte >> 32, flags);
361}
362extern int __must_check xen_event_channel_op_compat(int, void *);
363
364static inline int
365HYPERVISOR_event_channel_op(int cmd, void *arg)
366{
367	int rc = _hypercall2(int, event_channel_op, cmd, arg);
368	if (unlikely(rc == -ENOSYS))
369		rc = xen_event_channel_op_compat(cmd, arg);
370	return rc;
371}
372
373static inline int
374HYPERVISOR_xen_version(int cmd, void *arg)
375{
376	return _hypercall2(int, xen_version, cmd, arg);
377}
378
379static inline int
380HYPERVISOR_console_io(int cmd, int count, char *str)
381{
382	return _hypercall3(int, console_io, cmd, count, str);
383}
384
385extern int __must_check xen_physdev_op_compat(int, void *);
386
387static inline int
388HYPERVISOR_physdev_op(int cmd, void *arg)
389{
390	int rc = _hypercall2(int, physdev_op, cmd, arg);
391	if (unlikely(rc == -ENOSYS))
392		rc = xen_physdev_op_compat(cmd, arg);
393	return rc;
394}
395
396static inline int
397HYPERVISOR_grant_table_op(unsigned int cmd, void *uop, unsigned int count)
398{
399	return _hypercall3(int, grant_table_op, cmd, uop, count);
400}
401
402static inline int
403HYPERVISOR_update_va_mapping_otherdomain(unsigned long va, pte_t new_val,
404					 unsigned long flags, domid_t domid)
405{
406	if (sizeof(new_val) == sizeof(long))
407		return _hypercall4(int, update_va_mapping_otherdomain, va,
408				   new_val.pte, flags, domid);
409	else
410		return _hypercall5(int, update_va_mapping_otherdomain, va,
411				   new_val.pte, new_val.pte >> 32,
412				   flags, domid);
413}
414
415static inline int
416HYPERVISOR_vm_assist(unsigned int cmd, unsigned int type)
417{
418	return _hypercall2(int, vm_assist, cmd, type);
419}
420
421static inline int
422HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args)
423{
424	return _hypercall3(int, vcpu_op, cmd, vcpuid, extra_args);
425}
426
427#ifdef CONFIG_X86_64
428static inline int
429HYPERVISOR_set_segment_base(int reg, unsigned long value)
430{
431	return _hypercall2(int, set_segment_base, reg, value);
432}
433#endif
434
435static inline int
436HYPERVISOR_suspend(unsigned long start_info_mfn)
437{
438	struct sched_shutdown r = { .reason = SHUTDOWN_suspend };
439
440	/*
441	 * For a PV guest the tools require that the start_info mfn be
442	 * present in rdx/edx when the hypercall is made. Per the
443	 * hypercall calling convention this is the third hypercall
444	 * argument, which is start_info_mfn here.
445	 */
446	return _hypercall3(int, sched_op, SCHEDOP_shutdown, &r, start_info_mfn);
447}
448
449static inline int
450HYPERVISOR_nmi_op(unsigned long op, unsigned long arg)
451{
452	return _hypercall2(int, nmi_op, op, arg);
453}
454
455static inline unsigned long __must_check
456HYPERVISOR_hvm_op(int op, void *arg)
457{
458       return _hypercall2(unsigned long, hvm_op, op, arg);
459}
460
461static inline int
462HYPERVISOR_tmem_op(
463	struct tmem_op *op)
464{
465	return _hypercall1(int, tmem_op, op);
466}
467
468static inline void
469MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set)
470{
471	mcl->op = __HYPERVISOR_fpu_taskswitch;
472	mcl->args[0] = set;
473
474	trace_xen_mc_entry(mcl, 1);
475}
476
477static inline void
478MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va,
479			pte_t new_val, unsigned long flags)
480{
481	mcl->op = __HYPERVISOR_update_va_mapping;
482	mcl->args[0] = va;
483	if (sizeof(new_val) == sizeof(long)) {
484		mcl->args[1] = new_val.pte;
485		mcl->args[2] = flags;
486	} else {
487		mcl->args[1] = new_val.pte;
488		mcl->args[2] = new_val.pte >> 32;
489		mcl->args[3] = flags;
490	}
491
492	trace_xen_mc_entry(mcl, sizeof(new_val) == sizeof(long) ? 3 : 4);
493}
494
495static inline void
496MULTI_grant_table_op(struct multicall_entry *mcl, unsigned int cmd,
497		     void *uop, unsigned int count)
498{
499	mcl->op = __HYPERVISOR_grant_table_op;
500	mcl->args[0] = cmd;
501	mcl->args[1] = (unsigned long)uop;
502	mcl->args[2] = count;
503
504	trace_xen_mc_entry(mcl, 3);
505}
506
507static inline void
508MULTI_update_va_mapping_otherdomain(struct multicall_entry *mcl, unsigned long va,
509				    pte_t new_val, unsigned long flags,
510				    domid_t domid)
511{
512	mcl->op = __HYPERVISOR_update_va_mapping_otherdomain;
513	mcl->args[0] = va;
514	if (sizeof(new_val) == sizeof(long)) {
515		mcl->args[1] = new_val.pte;
516		mcl->args[2] = flags;
517		mcl->args[3] = domid;
518	} else {
519		mcl->args[1] = new_val.pte;
520		mcl->args[2] = new_val.pte >> 32;
521		mcl->args[3] = flags;
522		mcl->args[4] = domid;
523	}
524
525	trace_xen_mc_entry(mcl, sizeof(new_val) == sizeof(long) ? 4 : 5);
526}
527
528static inline void
529MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr,
530			struct desc_struct desc)
531{
532	mcl->op = __HYPERVISOR_update_descriptor;
533	if (sizeof(maddr) == sizeof(long)) {
534		mcl->args[0] = maddr;
535		mcl->args[1] = *(unsigned long *)&desc;
536	} else {
537		mcl->args[0] = maddr;
538		mcl->args[1] = maddr >> 32;
539		mcl->args[2] = desc.a;
540		mcl->args[3] = desc.b;
541	}
542
543	trace_xen_mc_entry(mcl, sizeof(maddr) == sizeof(long) ? 2 : 4);
544}
545
546static inline void
547MULTI_memory_op(struct multicall_entry *mcl, unsigned int cmd, void *arg)
548{
549	mcl->op = __HYPERVISOR_memory_op;
550	mcl->args[0] = cmd;
551	mcl->args[1] = (unsigned long)arg;
552
553	trace_xen_mc_entry(mcl, 2);
554}
555
556static inline void
557MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req,
558		 int count, int *success_count, domid_t domid)
559{
560	mcl->op = __HYPERVISOR_mmu_update;
561	mcl->args[0] = (unsigned long)req;
562	mcl->args[1] = count;
563	mcl->args[2] = (unsigned long)success_count;
564	mcl->args[3] = domid;
565
566	trace_xen_mc_entry(mcl, 4);
567}
568
569static inline void
570MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count,
571		int *success_count, domid_t domid)
572{
573	mcl->op = __HYPERVISOR_mmuext_op;
574	mcl->args[0] = (unsigned long)op;
575	mcl->args[1] = count;
576	mcl->args[2] = (unsigned long)success_count;
577	mcl->args[3] = domid;
578
579	trace_xen_mc_entry(mcl, 4);
580}
581
582static inline void
583MULTI_set_gdt(struct multicall_entry *mcl, unsigned long *frames, int entries)
584{
585	mcl->op = __HYPERVISOR_set_gdt;
586	mcl->args[0] = (unsigned long)frames;
587	mcl->args[1] = entries;
588
589	trace_xen_mc_entry(mcl, 2);
590}
591
592static inline void
593MULTI_stack_switch(struct multicall_entry *mcl,
594		   unsigned long ss, unsigned long esp)
595{
596	mcl->op = __HYPERVISOR_stack_switch;
597	mcl->args[0] = ss;
598	mcl->args[1] = esp;
599
600	trace_xen_mc_entry(mcl, 2);
601}
602
603#endif /* _ASM_X86_XEN_HYPERCALL_H */
604