xref: /openbmc/linux/arch/x86/include/asm/xen/hypercall.h (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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/errno.h>
37 #include <linux/string.h>
38 
39 #include <xen/interface/xen.h>
40 #include <xen/interface/sched.h>
41 #include <xen/interface/physdev.h>
42 
43 /*
44  * The hypercall asms have to meet several constraints:
45  * - Work on 32- and 64-bit.
46  *    The two architectures put their arguments in different sets of
47  *    registers.
48  *
49  * - Work around asm syntax quirks
50  *    It isn't possible to specify one of the rNN registers in a
51  *    constraint, so we use explicit register variables to get the
52  *    args into the right place.
53  *
54  * - Mark all registers as potentially clobbered
55  *    Even unused parameters can be clobbered by the hypervisor, so we
56  *    need to make sure gcc knows it.
57  *
58  * - Avoid compiler bugs.
59  *    This is the tricky part.  Because x86_32 has such a constrained
60  *    register set, gcc versions below 4.3 have trouble generating
61  *    code when all the arg registers and memory are trashed by the
62  *    asm.  There are syntactically simpler ways of achieving the
63  *    semantics below, but they cause the compiler to crash.
64  *
65  *    The only combination I found which works is:
66  *     - assign the __argX variables first
67  *     - list all actually used parameters as "+r" (__argX)
68  *     - clobber the rest
69  *
70  * The result certainly isn't pretty, and it really shows up cpp's
71  * weakness as as macro language.  Sorry.  (But let's just give thanks
72  * there aren't more than 5 arguments...)
73  */
74 
75 extern struct { char _entry[32]; } hypercall_page[];
76 
77 #define __HYPERCALL		"call hypercall_page+%c[offset]"
78 #define __HYPERCALL_ENTRY(x)						\
79 	[offset] "i" (__HYPERVISOR_##x * sizeof(hypercall_page[0]))
80 
81 #ifdef CONFIG_X86_32
82 #define __HYPERCALL_RETREG	"eax"
83 #define __HYPERCALL_ARG1REG	"ebx"
84 #define __HYPERCALL_ARG2REG	"ecx"
85 #define __HYPERCALL_ARG3REG	"edx"
86 #define __HYPERCALL_ARG4REG	"esi"
87 #define __HYPERCALL_ARG5REG	"edi"
88 #else
89 #define __HYPERCALL_RETREG	"rax"
90 #define __HYPERCALL_ARG1REG	"rdi"
91 #define __HYPERCALL_ARG2REG	"rsi"
92 #define __HYPERCALL_ARG3REG	"rdx"
93 #define __HYPERCALL_ARG4REG	"r10"
94 #define __HYPERCALL_ARG5REG	"r8"
95 #endif
96 
97 #define __HYPERCALL_DECLS						\
98 	register unsigned long __res  asm(__HYPERCALL_RETREG);		\
99 	register unsigned long __arg1 asm(__HYPERCALL_ARG1REG) = __arg1; \
100 	register unsigned long __arg2 asm(__HYPERCALL_ARG2REG) = __arg2; \
101 	register unsigned long __arg3 asm(__HYPERCALL_ARG3REG) = __arg3; \
102 	register unsigned long __arg4 asm(__HYPERCALL_ARG4REG) = __arg4; \
103 	register unsigned long __arg5 asm(__HYPERCALL_ARG5REG) = __arg5;
104 
105 #define __HYPERCALL_0PARAM	"=r" (__res)
106 #define __HYPERCALL_1PARAM	__HYPERCALL_0PARAM, "+r" (__arg1)
107 #define __HYPERCALL_2PARAM	__HYPERCALL_1PARAM, "+r" (__arg2)
108 #define __HYPERCALL_3PARAM	__HYPERCALL_2PARAM, "+r" (__arg3)
109 #define __HYPERCALL_4PARAM	__HYPERCALL_3PARAM, "+r" (__arg4)
110 #define __HYPERCALL_5PARAM	__HYPERCALL_4PARAM, "+r" (__arg5)
111 
112 #define __HYPERCALL_0ARG()
113 #define __HYPERCALL_1ARG(a1)						\
114 	__HYPERCALL_0ARG()		__arg1 = (unsigned long)(a1);
115 #define __HYPERCALL_2ARG(a1,a2)						\
116 	__HYPERCALL_1ARG(a1)		__arg2 = (unsigned long)(a2);
117 #define __HYPERCALL_3ARG(a1,a2,a3)					\
118 	__HYPERCALL_2ARG(a1,a2)		__arg3 = (unsigned long)(a3);
119 #define __HYPERCALL_4ARG(a1,a2,a3,a4)					\
120 	__HYPERCALL_3ARG(a1,a2,a3)	__arg4 = (unsigned long)(a4);
121 #define __HYPERCALL_5ARG(a1,a2,a3,a4,a5)				\
122 	__HYPERCALL_4ARG(a1,a2,a3,a4)	__arg5 = (unsigned long)(a5);
123 
124 #define __HYPERCALL_CLOBBER5	"memory"
125 #define __HYPERCALL_CLOBBER4	__HYPERCALL_CLOBBER5, __HYPERCALL_ARG5REG
126 #define __HYPERCALL_CLOBBER3	__HYPERCALL_CLOBBER4, __HYPERCALL_ARG4REG
127 #define __HYPERCALL_CLOBBER2	__HYPERCALL_CLOBBER3, __HYPERCALL_ARG3REG
128 #define __HYPERCALL_CLOBBER1	__HYPERCALL_CLOBBER2, __HYPERCALL_ARG2REG
129 #define __HYPERCALL_CLOBBER0	__HYPERCALL_CLOBBER1, __HYPERCALL_ARG1REG
130 
131 #define _hypercall0(type, name)						\
132 ({									\
133 	__HYPERCALL_DECLS;						\
134 	__HYPERCALL_0ARG();						\
135 	asm volatile (__HYPERCALL					\
136 		      : __HYPERCALL_0PARAM				\
137 		      : __HYPERCALL_ENTRY(name)				\
138 		      : __HYPERCALL_CLOBBER0);				\
139 	(type)__res;							\
140 })
141 
142 #define _hypercall1(type, name, a1)					\
143 ({									\
144 	__HYPERCALL_DECLS;						\
145 	__HYPERCALL_1ARG(a1);						\
146 	asm volatile (__HYPERCALL					\
147 		      : __HYPERCALL_1PARAM				\
148 		      : __HYPERCALL_ENTRY(name)				\
149 		      : __HYPERCALL_CLOBBER1);				\
150 	(type)__res;							\
151 })
152 
153 #define _hypercall2(type, name, a1, a2)					\
154 ({									\
155 	__HYPERCALL_DECLS;						\
156 	__HYPERCALL_2ARG(a1, a2);					\
157 	asm volatile (__HYPERCALL					\
158 		      : __HYPERCALL_2PARAM				\
159 		      : __HYPERCALL_ENTRY(name)				\
160 		      : __HYPERCALL_CLOBBER2);				\
161 	(type)__res;							\
162 })
163 
164 #define _hypercall3(type, name, a1, a2, a3)				\
165 ({									\
166 	__HYPERCALL_DECLS;						\
167 	__HYPERCALL_3ARG(a1, a2, a3);					\
168 	asm volatile (__HYPERCALL					\
169 		      : __HYPERCALL_3PARAM				\
170 		      : __HYPERCALL_ENTRY(name)				\
171 		      : __HYPERCALL_CLOBBER3);				\
172 	(type)__res;							\
173 })
174 
175 #define _hypercall4(type, name, a1, a2, a3, a4)				\
176 ({									\
177 	__HYPERCALL_DECLS;						\
178 	__HYPERCALL_4ARG(a1, a2, a3, a4);				\
179 	asm volatile (__HYPERCALL					\
180 		      : __HYPERCALL_4PARAM				\
181 		      : __HYPERCALL_ENTRY(name)				\
182 		      : __HYPERCALL_CLOBBER4);				\
183 	(type)__res;							\
184 })
185 
186 #define _hypercall5(type, name, a1, a2, a3, a4, a5)			\
187 ({									\
188 	__HYPERCALL_DECLS;						\
189 	__HYPERCALL_5ARG(a1, a2, a3, a4, a5);				\
190 	asm volatile (__HYPERCALL					\
191 		      : __HYPERCALL_5PARAM				\
192 		      : __HYPERCALL_ENTRY(name)				\
193 		      : __HYPERCALL_CLOBBER5);				\
194 	(type)__res;							\
195 })
196 
197 static inline int
198 HYPERVISOR_set_trap_table(struct trap_info *table)
199 {
200 	return _hypercall1(int, set_trap_table, table);
201 }
202 
203 static inline int
204 HYPERVISOR_mmu_update(struct mmu_update *req, int count,
205 		      int *success_count, domid_t domid)
206 {
207 	return _hypercall4(int, mmu_update, req, count, success_count, domid);
208 }
209 
210 static inline int
211 HYPERVISOR_mmuext_op(struct mmuext_op *op, int count,
212 		     int *success_count, domid_t domid)
213 {
214 	return _hypercall4(int, mmuext_op, op, count, success_count, domid);
215 }
216 
217 static inline int
218 HYPERVISOR_set_gdt(unsigned long *frame_list, int entries)
219 {
220 	return _hypercall2(int, set_gdt, frame_list, entries);
221 }
222 
223 static inline int
224 HYPERVISOR_stack_switch(unsigned long ss, unsigned long esp)
225 {
226 	return _hypercall2(int, stack_switch, ss, esp);
227 }
228 
229 #ifdef CONFIG_X86_32
230 static inline int
231 HYPERVISOR_set_callbacks(unsigned long event_selector,
232 			 unsigned long event_address,
233 			 unsigned long failsafe_selector,
234 			 unsigned long failsafe_address)
235 {
236 	return _hypercall4(int, set_callbacks,
237 			   event_selector, event_address,
238 			   failsafe_selector, failsafe_address);
239 }
240 #else  /* CONFIG_X86_64 */
241 static inline int
242 HYPERVISOR_set_callbacks(unsigned long event_address,
243 			unsigned long failsafe_address,
244 			unsigned long syscall_address)
245 {
246 	return _hypercall3(int, set_callbacks,
247 			   event_address, failsafe_address,
248 			   syscall_address);
249 }
250 #endif  /* CONFIG_X86_{32,64} */
251 
252 static inline int
253 HYPERVISOR_callback_op(int cmd, void *arg)
254 {
255 	return _hypercall2(int, callback_op, cmd, arg);
256 }
257 
258 static inline int
259 HYPERVISOR_fpu_taskswitch(int set)
260 {
261 	return _hypercall1(int, fpu_taskswitch, set);
262 }
263 
264 static inline int
265 HYPERVISOR_sched_op(int cmd, void *arg)
266 {
267 	return _hypercall2(int, sched_op_new, cmd, arg);
268 }
269 
270 static inline long
271 HYPERVISOR_set_timer_op(u64 timeout)
272 {
273 	unsigned long timeout_hi = (unsigned long)(timeout>>32);
274 	unsigned long timeout_lo = (unsigned long)timeout;
275 	return _hypercall2(long, set_timer_op, timeout_lo, timeout_hi);
276 }
277 
278 static inline int
279 HYPERVISOR_set_debugreg(int reg, unsigned long value)
280 {
281 	return _hypercall2(int, set_debugreg, reg, value);
282 }
283 
284 static inline unsigned long
285 HYPERVISOR_get_debugreg(int reg)
286 {
287 	return _hypercall1(unsigned long, get_debugreg, reg);
288 }
289 
290 static inline int
291 HYPERVISOR_update_descriptor(u64 ma, u64 desc)
292 {
293 	return _hypercall4(int, update_descriptor, ma, ma>>32, desc, desc>>32);
294 }
295 
296 static inline int
297 HYPERVISOR_memory_op(unsigned int cmd, void *arg)
298 {
299 	return _hypercall2(int, memory_op, cmd, arg);
300 }
301 
302 static inline int
303 HYPERVISOR_multicall(void *call_list, int nr_calls)
304 {
305 	return _hypercall2(int, multicall, call_list, nr_calls);
306 }
307 
308 static inline int
309 HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val,
310 			     unsigned long flags)
311 {
312 	if (sizeof(new_val) == sizeof(long))
313 		return _hypercall3(int, update_va_mapping, va,
314 				   new_val.pte, flags);
315 	else
316 		return _hypercall4(int, update_va_mapping, va,
317 				   new_val.pte, new_val.pte >> 32, flags);
318 }
319 
320 static inline int
321 HYPERVISOR_event_channel_op(int cmd, void *arg)
322 {
323 	int rc = _hypercall2(int, event_channel_op, cmd, arg);
324 	if (unlikely(rc == -ENOSYS)) {
325 		struct evtchn_op op;
326 		op.cmd = cmd;
327 		memcpy(&op.u, arg, sizeof(op.u));
328 		rc = _hypercall1(int, event_channel_op_compat, &op);
329 		memcpy(arg, &op.u, sizeof(op.u));
330 	}
331 	return rc;
332 }
333 
334 static inline int
335 HYPERVISOR_xen_version(int cmd, void *arg)
336 {
337 	return _hypercall2(int, xen_version, cmd, arg);
338 }
339 
340 static inline int
341 HYPERVISOR_console_io(int cmd, int count, char *str)
342 {
343 	return _hypercall3(int, console_io, cmd, count, str);
344 }
345 
346 static inline int
347 HYPERVISOR_physdev_op(int cmd, void *arg)
348 {
349 	int rc = _hypercall2(int, physdev_op, cmd, arg);
350 	if (unlikely(rc == -ENOSYS)) {
351 		struct physdev_op op;
352 		op.cmd = cmd;
353 		memcpy(&op.u, arg, sizeof(op.u));
354 		rc = _hypercall1(int, physdev_op_compat, &op);
355 		memcpy(arg, &op.u, sizeof(op.u));
356 	}
357 	return rc;
358 }
359 
360 static inline int
361 HYPERVISOR_grant_table_op(unsigned int cmd, void *uop, unsigned int count)
362 {
363 	return _hypercall3(int, grant_table_op, cmd, uop, count);
364 }
365 
366 static inline int
367 HYPERVISOR_update_va_mapping_otherdomain(unsigned long va, pte_t new_val,
368 					 unsigned long flags, domid_t domid)
369 {
370 	if (sizeof(new_val) == sizeof(long))
371 		return _hypercall4(int, update_va_mapping_otherdomain, va,
372 				   new_val.pte, flags, domid);
373 	else
374 		return _hypercall5(int, update_va_mapping_otherdomain, va,
375 				   new_val.pte, new_val.pte >> 32,
376 				   flags, domid);
377 }
378 
379 static inline int
380 HYPERVISOR_vm_assist(unsigned int cmd, unsigned int type)
381 {
382 	return _hypercall2(int, vm_assist, cmd, type);
383 }
384 
385 static inline int
386 HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args)
387 {
388 	return _hypercall3(int, vcpu_op, cmd, vcpuid, extra_args);
389 }
390 
391 #ifdef CONFIG_X86_64
392 static inline int
393 HYPERVISOR_set_segment_base(int reg, unsigned long value)
394 {
395 	return _hypercall2(int, set_segment_base, reg, value);
396 }
397 #endif
398 
399 static inline int
400 HYPERVISOR_suspend(unsigned long srec)
401 {
402 	return _hypercall3(int, sched_op, SCHEDOP_shutdown,
403 			   SHUTDOWN_suspend, srec);
404 }
405 
406 static inline int
407 HYPERVISOR_nmi_op(unsigned long op, unsigned long arg)
408 {
409 	return _hypercall2(int, nmi_op, op, arg);
410 }
411 
412 static inline void
413 MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set)
414 {
415 	mcl->op = __HYPERVISOR_fpu_taskswitch;
416 	mcl->args[0] = set;
417 }
418 
419 static inline void
420 MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va,
421 			pte_t new_val, unsigned long flags)
422 {
423 	mcl->op = __HYPERVISOR_update_va_mapping;
424 	mcl->args[0] = va;
425 	if (sizeof(new_val) == sizeof(long)) {
426 		mcl->args[1] = new_val.pte;
427 		mcl->args[2] = flags;
428 	} else {
429 		mcl->args[1] = new_val.pte;
430 		mcl->args[2] = new_val.pte >> 32;
431 		mcl->args[3] = flags;
432 	}
433 }
434 
435 static inline void
436 MULTI_grant_table_op(struct multicall_entry *mcl, unsigned int cmd,
437 		     void *uop, unsigned int count)
438 {
439 	mcl->op = __HYPERVISOR_grant_table_op;
440 	mcl->args[0] = cmd;
441 	mcl->args[1] = (unsigned long)uop;
442 	mcl->args[2] = count;
443 }
444 
445 static inline void
446 MULTI_update_va_mapping_otherdomain(struct multicall_entry *mcl, unsigned long va,
447 				    pte_t new_val, unsigned long flags,
448 				    domid_t domid)
449 {
450 	mcl->op = __HYPERVISOR_update_va_mapping_otherdomain;
451 	mcl->args[0] = va;
452 	if (sizeof(new_val) == sizeof(long)) {
453 		mcl->args[1] = new_val.pte;
454 		mcl->args[2] = flags;
455 		mcl->args[3] = domid;
456 	} else {
457 		mcl->args[1] = new_val.pte;
458 		mcl->args[2] = new_val.pte >> 32;
459 		mcl->args[3] = flags;
460 		mcl->args[4] = domid;
461 	}
462 }
463 
464 static inline void
465 MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr,
466 			struct desc_struct desc)
467 {
468 	mcl->op = __HYPERVISOR_update_descriptor;
469 	if (sizeof(maddr) == sizeof(long)) {
470 		mcl->args[0] = maddr;
471 		mcl->args[1] = *(unsigned long *)&desc;
472 	} else {
473 		mcl->args[0] = maddr;
474 		mcl->args[1] = maddr >> 32;
475 		mcl->args[2] = desc.a;
476 		mcl->args[3] = desc.b;
477 	}
478 }
479 
480 static inline void
481 MULTI_memory_op(struct multicall_entry *mcl, unsigned int cmd, void *arg)
482 {
483 	mcl->op = __HYPERVISOR_memory_op;
484 	mcl->args[0] = cmd;
485 	mcl->args[1] = (unsigned long)arg;
486 }
487 
488 static inline void
489 MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req,
490 		 int count, int *success_count, domid_t domid)
491 {
492 	mcl->op = __HYPERVISOR_mmu_update;
493 	mcl->args[0] = (unsigned long)req;
494 	mcl->args[1] = count;
495 	mcl->args[2] = (unsigned long)success_count;
496 	mcl->args[3] = domid;
497 }
498 
499 static inline void
500 MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count,
501 		int *success_count, domid_t domid)
502 {
503 	mcl->op = __HYPERVISOR_mmuext_op;
504 	mcl->args[0] = (unsigned long)op;
505 	mcl->args[1] = count;
506 	mcl->args[2] = (unsigned long)success_count;
507 	mcl->args[3] = domid;
508 }
509 
510 static inline void
511 MULTI_set_gdt(struct multicall_entry *mcl, unsigned long *frames, int entries)
512 {
513 	mcl->op = __HYPERVISOR_set_gdt;
514 	mcl->args[0] = (unsigned long)frames;
515 	mcl->args[1] = entries;
516 }
517 
518 static inline void
519 MULTI_stack_switch(struct multicall_entry *mcl,
520 		   unsigned long ss, unsigned long esp)
521 {
522 	mcl->op = __HYPERVISOR_stack_switch;
523 	mcl->args[0] = ss;
524 	mcl->args[1] = esp;
525 }
526 
527 #endif /* _ASM_X86_XEN_HYPERCALL_H */
528