xref: /openbmc/linux/arch/x86/include/asm/xen/hypercall.h (revision ecba1060)
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 <asm/page.h>
43 #include <asm/pgtable.h>
44 
45 #include <xen/interface/xen.h>
46 #include <xen/interface/sched.h>
47 #include <xen/interface/physdev.h>
48 
49 /*
50  * The hypercall asms have to meet several constraints:
51  * - Work on 32- and 64-bit.
52  *    The two architectures put their arguments in different sets of
53  *    registers.
54  *
55  * - Work around asm syntax quirks
56  *    It isn't possible to specify one of the rNN registers in a
57  *    constraint, so we use explicit register variables to get the
58  *    args into the right place.
59  *
60  * - Mark all registers as potentially clobbered
61  *    Even unused parameters can be clobbered by the hypervisor, so we
62  *    need to make sure gcc knows it.
63  *
64  * - Avoid compiler bugs.
65  *    This is the tricky part.  Because x86_32 has such a constrained
66  *    register set, gcc versions below 4.3 have trouble generating
67  *    code when all the arg registers and memory are trashed by the
68  *    asm.  There are syntactically simpler ways of achieving the
69  *    semantics below, but they cause the compiler to crash.
70  *
71  *    The only combination I found which works is:
72  *     - assign the __argX variables first
73  *     - list all actually used parameters as "+r" (__argX)
74  *     - clobber the rest
75  *
76  * The result certainly isn't pretty, and it really shows up cpp's
77  * weakness as as macro language.  Sorry.  (But let's just give thanks
78  * there aren't more than 5 arguments...)
79  */
80 
81 extern struct { char _entry[32]; } hypercall_page[];
82 
83 #define __HYPERCALL		"call hypercall_page+%c[offset]"
84 #define __HYPERCALL_ENTRY(x)						\
85 	[offset] "i" (__HYPERVISOR_##x * sizeof(hypercall_page[0]))
86 
87 #ifdef CONFIG_X86_32
88 #define __HYPERCALL_RETREG	"eax"
89 #define __HYPERCALL_ARG1REG	"ebx"
90 #define __HYPERCALL_ARG2REG	"ecx"
91 #define __HYPERCALL_ARG3REG	"edx"
92 #define __HYPERCALL_ARG4REG	"esi"
93 #define __HYPERCALL_ARG5REG	"edi"
94 #else
95 #define __HYPERCALL_RETREG	"rax"
96 #define __HYPERCALL_ARG1REG	"rdi"
97 #define __HYPERCALL_ARG2REG	"rsi"
98 #define __HYPERCALL_ARG3REG	"rdx"
99 #define __HYPERCALL_ARG4REG	"r10"
100 #define __HYPERCALL_ARG5REG	"r8"
101 #endif
102 
103 #define __HYPERCALL_DECLS						\
104 	register unsigned long __res  asm(__HYPERCALL_RETREG);		\
105 	register unsigned long __arg1 asm(__HYPERCALL_ARG1REG) = __arg1; \
106 	register unsigned long __arg2 asm(__HYPERCALL_ARG2REG) = __arg2; \
107 	register unsigned long __arg3 asm(__HYPERCALL_ARG3REG) = __arg3; \
108 	register unsigned long __arg4 asm(__HYPERCALL_ARG4REG) = __arg4; \
109 	register unsigned long __arg5 asm(__HYPERCALL_ARG5REG) = __arg5;
110 
111 #define __HYPERCALL_0PARAM	"=r" (__res)
112 #define __HYPERCALL_1PARAM	__HYPERCALL_0PARAM, "+r" (__arg1)
113 #define __HYPERCALL_2PARAM	__HYPERCALL_1PARAM, "+r" (__arg2)
114 #define __HYPERCALL_3PARAM	__HYPERCALL_2PARAM, "+r" (__arg3)
115 #define __HYPERCALL_4PARAM	__HYPERCALL_3PARAM, "+r" (__arg4)
116 #define __HYPERCALL_5PARAM	__HYPERCALL_4PARAM, "+r" (__arg5)
117 
118 #define __HYPERCALL_0ARG()
119 #define __HYPERCALL_1ARG(a1)						\
120 	__HYPERCALL_0ARG()		__arg1 = (unsigned long)(a1);
121 #define __HYPERCALL_2ARG(a1,a2)						\
122 	__HYPERCALL_1ARG(a1)		__arg2 = (unsigned long)(a2);
123 #define __HYPERCALL_3ARG(a1,a2,a3)					\
124 	__HYPERCALL_2ARG(a1,a2)		__arg3 = (unsigned long)(a3);
125 #define __HYPERCALL_4ARG(a1,a2,a3,a4)					\
126 	__HYPERCALL_3ARG(a1,a2,a3)	__arg4 = (unsigned long)(a4);
127 #define __HYPERCALL_5ARG(a1,a2,a3,a4,a5)				\
128 	__HYPERCALL_4ARG(a1,a2,a3,a4)	__arg5 = (unsigned long)(a5);
129 
130 #define __HYPERCALL_CLOBBER5	"memory"
131 #define __HYPERCALL_CLOBBER4	__HYPERCALL_CLOBBER5, __HYPERCALL_ARG5REG
132 #define __HYPERCALL_CLOBBER3	__HYPERCALL_CLOBBER4, __HYPERCALL_ARG4REG
133 #define __HYPERCALL_CLOBBER2	__HYPERCALL_CLOBBER3, __HYPERCALL_ARG3REG
134 #define __HYPERCALL_CLOBBER1	__HYPERCALL_CLOBBER2, __HYPERCALL_ARG2REG
135 #define __HYPERCALL_CLOBBER0	__HYPERCALL_CLOBBER1, __HYPERCALL_ARG1REG
136 
137 #define _hypercall0(type, name)						\
138 ({									\
139 	__HYPERCALL_DECLS;						\
140 	__HYPERCALL_0ARG();						\
141 	asm volatile (__HYPERCALL					\
142 		      : __HYPERCALL_0PARAM				\
143 		      : __HYPERCALL_ENTRY(name)				\
144 		      : __HYPERCALL_CLOBBER0);				\
145 	(type)__res;							\
146 })
147 
148 #define _hypercall1(type, name, a1)					\
149 ({									\
150 	__HYPERCALL_DECLS;						\
151 	__HYPERCALL_1ARG(a1);						\
152 	asm volatile (__HYPERCALL					\
153 		      : __HYPERCALL_1PARAM				\
154 		      : __HYPERCALL_ENTRY(name)				\
155 		      : __HYPERCALL_CLOBBER1);				\
156 	(type)__res;							\
157 })
158 
159 #define _hypercall2(type, name, a1, a2)					\
160 ({									\
161 	__HYPERCALL_DECLS;						\
162 	__HYPERCALL_2ARG(a1, a2);					\
163 	asm volatile (__HYPERCALL					\
164 		      : __HYPERCALL_2PARAM				\
165 		      : __HYPERCALL_ENTRY(name)				\
166 		      : __HYPERCALL_CLOBBER2);				\
167 	(type)__res;							\
168 })
169 
170 #define _hypercall3(type, name, a1, a2, a3)				\
171 ({									\
172 	__HYPERCALL_DECLS;						\
173 	__HYPERCALL_3ARG(a1, a2, a3);					\
174 	asm volatile (__HYPERCALL					\
175 		      : __HYPERCALL_3PARAM				\
176 		      : __HYPERCALL_ENTRY(name)				\
177 		      : __HYPERCALL_CLOBBER3);				\
178 	(type)__res;							\
179 })
180 
181 #define _hypercall4(type, name, a1, a2, a3, a4)				\
182 ({									\
183 	__HYPERCALL_DECLS;						\
184 	__HYPERCALL_4ARG(a1, a2, a3, a4);				\
185 	asm volatile (__HYPERCALL					\
186 		      : __HYPERCALL_4PARAM				\
187 		      : __HYPERCALL_ENTRY(name)				\
188 		      : __HYPERCALL_CLOBBER4);				\
189 	(type)__res;							\
190 })
191 
192 #define _hypercall5(type, name, a1, a2, a3, a4, a5)			\
193 ({									\
194 	__HYPERCALL_DECLS;						\
195 	__HYPERCALL_5ARG(a1, a2, a3, a4, a5);				\
196 	asm volatile (__HYPERCALL					\
197 		      : __HYPERCALL_5PARAM				\
198 		      : __HYPERCALL_ENTRY(name)				\
199 		      : __HYPERCALL_CLOBBER5);				\
200 	(type)__res;							\
201 })
202 
203 static inline int
204 HYPERVISOR_set_trap_table(struct trap_info *table)
205 {
206 	return _hypercall1(int, set_trap_table, table);
207 }
208 
209 static inline int
210 HYPERVISOR_mmu_update(struct mmu_update *req, int count,
211 		      int *success_count, domid_t domid)
212 {
213 	return _hypercall4(int, mmu_update, req, count, success_count, domid);
214 }
215 
216 static inline int
217 HYPERVISOR_mmuext_op(struct mmuext_op *op, int count,
218 		     int *success_count, domid_t domid)
219 {
220 	return _hypercall4(int, mmuext_op, op, count, success_count, domid);
221 }
222 
223 static inline int
224 HYPERVISOR_set_gdt(unsigned long *frame_list, int entries)
225 {
226 	return _hypercall2(int, set_gdt, frame_list, entries);
227 }
228 
229 static inline int
230 HYPERVISOR_stack_switch(unsigned long ss, unsigned long esp)
231 {
232 	return _hypercall2(int, stack_switch, ss, esp);
233 }
234 
235 #ifdef CONFIG_X86_32
236 static inline int
237 HYPERVISOR_set_callbacks(unsigned long event_selector,
238 			 unsigned long event_address,
239 			 unsigned long failsafe_selector,
240 			 unsigned long failsafe_address)
241 {
242 	return _hypercall4(int, set_callbacks,
243 			   event_selector, event_address,
244 			   failsafe_selector, failsafe_address);
245 }
246 #else  /* CONFIG_X86_64 */
247 static inline int
248 HYPERVISOR_set_callbacks(unsigned long event_address,
249 			unsigned long failsafe_address,
250 			unsigned long syscall_address)
251 {
252 	return _hypercall3(int, set_callbacks,
253 			   event_address, failsafe_address,
254 			   syscall_address);
255 }
256 #endif  /* CONFIG_X86_{32,64} */
257 
258 static inline int
259 HYPERVISOR_callback_op(int cmd, void *arg)
260 {
261 	return _hypercall2(int, callback_op, cmd, arg);
262 }
263 
264 static inline int
265 HYPERVISOR_fpu_taskswitch(int set)
266 {
267 	return _hypercall1(int, fpu_taskswitch, set);
268 }
269 
270 static inline int
271 HYPERVISOR_sched_op(int cmd, void *arg)
272 {
273 	return _hypercall2(int, sched_op_new, cmd, arg);
274 }
275 
276 static inline long
277 HYPERVISOR_set_timer_op(u64 timeout)
278 {
279 	unsigned long timeout_hi = (unsigned long)(timeout>>32);
280 	unsigned long timeout_lo = (unsigned long)timeout;
281 	return _hypercall2(long, set_timer_op, timeout_lo, timeout_hi);
282 }
283 
284 static inline int
285 HYPERVISOR_set_debugreg(int reg, unsigned long value)
286 {
287 	return _hypercall2(int, set_debugreg, reg, value);
288 }
289 
290 static inline unsigned long
291 HYPERVISOR_get_debugreg(int reg)
292 {
293 	return _hypercall1(unsigned long, get_debugreg, reg);
294 }
295 
296 static inline int
297 HYPERVISOR_update_descriptor(u64 ma, u64 desc)
298 {
299 	if (sizeof(u64) == sizeof(long))
300 		return _hypercall2(int, update_descriptor, ma, desc);
301 	return _hypercall4(int, update_descriptor, ma, ma>>32, desc, desc>>32);
302 }
303 
304 static inline int
305 HYPERVISOR_memory_op(unsigned int cmd, void *arg)
306 {
307 	return _hypercall2(int, memory_op, cmd, arg);
308 }
309 
310 static inline int
311 HYPERVISOR_multicall(void *call_list, int nr_calls)
312 {
313 	return _hypercall2(int, multicall, call_list, nr_calls);
314 }
315 
316 static inline int
317 HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val,
318 			     unsigned long flags)
319 {
320 	if (sizeof(new_val) == sizeof(long))
321 		return _hypercall3(int, update_va_mapping, va,
322 				   new_val.pte, flags);
323 	else
324 		return _hypercall4(int, update_va_mapping, va,
325 				   new_val.pte, new_val.pte >> 32, flags);
326 }
327 
328 static inline int
329 HYPERVISOR_event_channel_op(int cmd, void *arg)
330 {
331 	int rc = _hypercall2(int, event_channel_op, cmd, arg);
332 	if (unlikely(rc == -ENOSYS)) {
333 		struct evtchn_op op;
334 		op.cmd = cmd;
335 		memcpy(&op.u, arg, sizeof(op.u));
336 		rc = _hypercall1(int, event_channel_op_compat, &op);
337 		memcpy(arg, &op.u, sizeof(op.u));
338 	}
339 	return rc;
340 }
341 
342 static inline int
343 HYPERVISOR_xen_version(int cmd, void *arg)
344 {
345 	return _hypercall2(int, xen_version, cmd, arg);
346 }
347 
348 static inline int
349 HYPERVISOR_console_io(int cmd, int count, char *str)
350 {
351 	return _hypercall3(int, console_io, cmd, count, str);
352 }
353 
354 static inline int
355 HYPERVISOR_physdev_op(int cmd, void *arg)
356 {
357 	int rc = _hypercall2(int, physdev_op, cmd, arg);
358 	if (unlikely(rc == -ENOSYS)) {
359 		struct physdev_op op;
360 		op.cmd = cmd;
361 		memcpy(&op.u, arg, sizeof(op.u));
362 		rc = _hypercall1(int, physdev_op_compat, &op);
363 		memcpy(arg, &op.u, sizeof(op.u));
364 	}
365 	return rc;
366 }
367 
368 static inline int
369 HYPERVISOR_grant_table_op(unsigned int cmd, void *uop, unsigned int count)
370 {
371 	return _hypercall3(int, grant_table_op, cmd, uop, count);
372 }
373 
374 static inline int
375 HYPERVISOR_update_va_mapping_otherdomain(unsigned long va, pte_t new_val,
376 					 unsigned long flags, domid_t domid)
377 {
378 	if (sizeof(new_val) == sizeof(long))
379 		return _hypercall4(int, update_va_mapping_otherdomain, va,
380 				   new_val.pte, flags, domid);
381 	else
382 		return _hypercall5(int, update_va_mapping_otherdomain, va,
383 				   new_val.pte, new_val.pte >> 32,
384 				   flags, domid);
385 }
386 
387 static inline int
388 HYPERVISOR_vm_assist(unsigned int cmd, unsigned int type)
389 {
390 	return _hypercall2(int, vm_assist, cmd, type);
391 }
392 
393 static inline int
394 HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args)
395 {
396 	return _hypercall3(int, vcpu_op, cmd, vcpuid, extra_args);
397 }
398 
399 #ifdef CONFIG_X86_64
400 static inline int
401 HYPERVISOR_set_segment_base(int reg, unsigned long value)
402 {
403 	return _hypercall2(int, set_segment_base, reg, value);
404 }
405 #endif
406 
407 static inline int
408 HYPERVISOR_suspend(unsigned long srec)
409 {
410 	return _hypercall3(int, sched_op, SCHEDOP_shutdown,
411 			   SHUTDOWN_suspend, srec);
412 }
413 
414 static inline int
415 HYPERVISOR_nmi_op(unsigned long op, unsigned long arg)
416 {
417 	return _hypercall2(int, nmi_op, op, arg);
418 }
419 
420 static inline void
421 MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set)
422 {
423 	mcl->op = __HYPERVISOR_fpu_taskswitch;
424 	mcl->args[0] = set;
425 }
426 
427 static inline void
428 MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va,
429 			pte_t new_val, unsigned long flags)
430 {
431 	mcl->op = __HYPERVISOR_update_va_mapping;
432 	mcl->args[0] = va;
433 	if (sizeof(new_val) == sizeof(long)) {
434 		mcl->args[1] = new_val.pte;
435 		mcl->args[2] = flags;
436 	} else {
437 		mcl->args[1] = new_val.pte;
438 		mcl->args[2] = new_val.pte >> 32;
439 		mcl->args[3] = flags;
440 	}
441 }
442 
443 static inline void
444 MULTI_grant_table_op(struct multicall_entry *mcl, unsigned int cmd,
445 		     void *uop, unsigned int count)
446 {
447 	mcl->op = __HYPERVISOR_grant_table_op;
448 	mcl->args[0] = cmd;
449 	mcl->args[1] = (unsigned long)uop;
450 	mcl->args[2] = count;
451 }
452 
453 static inline void
454 MULTI_update_va_mapping_otherdomain(struct multicall_entry *mcl, unsigned long va,
455 				    pte_t new_val, unsigned long flags,
456 				    domid_t domid)
457 {
458 	mcl->op = __HYPERVISOR_update_va_mapping_otherdomain;
459 	mcl->args[0] = va;
460 	if (sizeof(new_val) == sizeof(long)) {
461 		mcl->args[1] = new_val.pte;
462 		mcl->args[2] = flags;
463 		mcl->args[3] = domid;
464 	} else {
465 		mcl->args[1] = new_val.pte;
466 		mcl->args[2] = new_val.pte >> 32;
467 		mcl->args[3] = flags;
468 		mcl->args[4] = domid;
469 	}
470 }
471 
472 static inline void
473 MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr,
474 			struct desc_struct desc)
475 {
476 	mcl->op = __HYPERVISOR_update_descriptor;
477 	if (sizeof(maddr) == sizeof(long)) {
478 		mcl->args[0] = maddr;
479 		mcl->args[1] = *(unsigned long *)&desc;
480 	} else {
481 		mcl->args[0] = maddr;
482 		mcl->args[1] = maddr >> 32;
483 		mcl->args[2] = desc.a;
484 		mcl->args[3] = desc.b;
485 	}
486 }
487 
488 static inline void
489 MULTI_memory_op(struct multicall_entry *mcl, unsigned int cmd, void *arg)
490 {
491 	mcl->op = __HYPERVISOR_memory_op;
492 	mcl->args[0] = cmd;
493 	mcl->args[1] = (unsigned long)arg;
494 }
495 
496 static inline void
497 MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req,
498 		 int count, int *success_count, domid_t domid)
499 {
500 	mcl->op = __HYPERVISOR_mmu_update;
501 	mcl->args[0] = (unsigned long)req;
502 	mcl->args[1] = count;
503 	mcl->args[2] = (unsigned long)success_count;
504 	mcl->args[3] = domid;
505 }
506 
507 static inline void
508 MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count,
509 		int *success_count, domid_t domid)
510 {
511 	mcl->op = __HYPERVISOR_mmuext_op;
512 	mcl->args[0] = (unsigned long)op;
513 	mcl->args[1] = count;
514 	mcl->args[2] = (unsigned long)success_count;
515 	mcl->args[3] = domid;
516 }
517 
518 static inline void
519 MULTI_set_gdt(struct multicall_entry *mcl, unsigned long *frames, int entries)
520 {
521 	mcl->op = __HYPERVISOR_set_gdt;
522 	mcl->args[0] = (unsigned long)frames;
523 	mcl->args[1] = entries;
524 }
525 
526 static inline void
527 MULTI_stack_switch(struct multicall_entry *mcl,
528 		   unsigned long ss, unsigned long esp)
529 {
530 	mcl->op = __HYPERVISOR_stack_switch;
531 	mcl->args[0] = ss;
532 	mcl->args[1] = esp;
533 }
534 
535 #endif /* _ASM_X86_XEN_HYPERCALL_H */
536