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 | #include <linux/pgtable.h> |
42 | |
43 | #include <trace/events/xen.h> |
44 | |
45 | #include <asm/page.h> |
46 | #include <asm/smap.h> |
47 | #include <asm/nospec-branch.h> |
48 | |
49 | #include <xen/interface/xen.h> |
50 | #include <xen/interface/sched.h> |
51 | #include <xen/interface/physdev.h> |
52 | #include <xen/interface/platform.h> |
53 | #include <xen/interface/xen-mca.h> |
54 | |
55 | struct xen_dm_op_buf; |
56 | |
57 | /* |
58 | * The hypercall asms have to meet several constraints: |
59 | * - Work on 32- and 64-bit. |
60 | * The two architectures put their arguments in different sets of |
61 | * registers. |
62 | * |
63 | * - Work around asm syntax quirks |
64 | * It isn't possible to specify one of the rNN registers in a |
65 | * constraint, so we use explicit register variables to get the |
66 | * args into the right place. |
67 | * |
68 | * - Mark all registers as potentially clobbered |
69 | * Even unused parameters can be clobbered by the hypervisor, so we |
70 | * need to make sure gcc knows it. |
71 | * |
72 | * - Avoid compiler bugs. |
73 | * This is the tricky part. Because x86_32 has such a constrained |
74 | * register set, gcc versions below 4.3 have trouble generating |
75 | * code when all the arg registers and memory are trashed by the |
76 | * asm. There are syntactically simpler ways of achieving the |
77 | * semantics below, but they cause the compiler to crash. |
78 | * |
79 | * The only combination I found which works is: |
80 | * - assign the __argX variables first |
81 | * - list all actually used parameters as "+r" (__argX) |
82 | * - clobber the rest |
83 | * |
84 | * The result certainly isn't pretty, and it really shows up cpp's |
85 | * weakness as a macro language. Sorry. (But let's just give thanks |
86 | * there aren't more than 5 arguments...) |
87 | */ |
88 | |
89 | extern struct { char _entry[32]; } hypercall_page[]; |
90 | |
91 | #define __HYPERCALL "call hypercall_page+%c[offset]" |
92 | #define __HYPERCALL_ENTRY(x) \ |
93 | [offset] "i" (__HYPERVISOR_##x * sizeof(hypercall_page[0])) |
94 | |
95 | #ifdef CONFIG_X86_32 |
96 | #define __HYPERCALL_RETREG "eax" |
97 | #define __HYPERCALL_ARG1REG "ebx" |
98 | #define __HYPERCALL_ARG2REG "ecx" |
99 | #define __HYPERCALL_ARG3REG "edx" |
100 | #define __HYPERCALL_ARG4REG "esi" |
101 | #define __HYPERCALL_ARG5REG "edi" |
102 | #else |
103 | #define __HYPERCALL_RETREG "rax" |
104 | #define __HYPERCALL_ARG1REG "rdi" |
105 | #define __HYPERCALL_ARG2REG "rsi" |
106 | #define __HYPERCALL_ARG3REG "rdx" |
107 | #define __HYPERCALL_ARG4REG "r10" |
108 | #define __HYPERCALL_ARG5REG "r8" |
109 | #endif |
110 | |
111 | #define __HYPERCALL_DECLS \ |
112 | register unsigned long __res asm(__HYPERCALL_RETREG); \ |
113 | register unsigned long __arg1 asm(__HYPERCALL_ARG1REG) = __arg1; \ |
114 | register unsigned long __arg2 asm(__HYPERCALL_ARG2REG) = __arg2; \ |
115 | register unsigned long __arg3 asm(__HYPERCALL_ARG3REG) = __arg3; \ |
116 | register unsigned long __arg4 asm(__HYPERCALL_ARG4REG) = __arg4; \ |
117 | register unsigned long __arg5 asm(__HYPERCALL_ARG5REG) = __arg5; |
118 | |
119 | #define __HYPERCALL_0PARAM "=r" (__res), ASM_CALL_CONSTRAINT |
120 | #define __HYPERCALL_1PARAM __HYPERCALL_0PARAM, "+r" (__arg1) |
121 | #define __HYPERCALL_2PARAM __HYPERCALL_1PARAM, "+r" (__arg2) |
122 | #define __HYPERCALL_3PARAM __HYPERCALL_2PARAM, "+r" (__arg3) |
123 | #define __HYPERCALL_4PARAM __HYPERCALL_3PARAM, "+r" (__arg4) |
124 | #define __HYPERCALL_5PARAM __HYPERCALL_4PARAM, "+r" (__arg5) |
125 | |
126 | #define __HYPERCALL_0ARG() |
127 | #define __HYPERCALL_1ARG(a1) \ |
128 | __HYPERCALL_0ARG() __arg1 = (unsigned long)(a1); |
129 | #define __HYPERCALL_2ARG(a1,a2) \ |
130 | __HYPERCALL_1ARG(a1) __arg2 = (unsigned long)(a2); |
131 | #define __HYPERCALL_3ARG(a1,a2,a3) \ |
132 | __HYPERCALL_2ARG(a1,a2) __arg3 = (unsigned long)(a3); |
133 | #define __HYPERCALL_4ARG(a1,a2,a3,a4) \ |
134 | __HYPERCALL_3ARG(a1,a2,a3) __arg4 = (unsigned long)(a4); |
135 | #define __HYPERCALL_5ARG(a1,a2,a3,a4,a5) \ |
136 | __HYPERCALL_4ARG(a1,a2,a3,a4) __arg5 = (unsigned long)(a5); |
137 | |
138 | #define __HYPERCALL_CLOBBER5 "memory" |
139 | #define __HYPERCALL_CLOBBER4 __HYPERCALL_CLOBBER5, __HYPERCALL_ARG5REG |
140 | #define __HYPERCALL_CLOBBER3 __HYPERCALL_CLOBBER4, __HYPERCALL_ARG4REG |
141 | #define __HYPERCALL_CLOBBER2 __HYPERCALL_CLOBBER3, __HYPERCALL_ARG3REG |
142 | #define __HYPERCALL_CLOBBER1 __HYPERCALL_CLOBBER2, __HYPERCALL_ARG2REG |
143 | #define __HYPERCALL_CLOBBER0 __HYPERCALL_CLOBBER1, __HYPERCALL_ARG1REG |
144 | |
145 | #define _hypercall0(type, name) \ |
146 | ({ \ |
147 | __HYPERCALL_DECLS; \ |
148 | __HYPERCALL_0ARG(); \ |
149 | asm volatile (__HYPERCALL \ |
150 | : __HYPERCALL_0PARAM \ |
151 | : __HYPERCALL_ENTRY(name) \ |
152 | : __HYPERCALL_CLOBBER0); \ |
153 | (type)__res; \ |
154 | }) |
155 | |
156 | #define _hypercall1(type, name, a1) \ |
157 | ({ \ |
158 | __HYPERCALL_DECLS; \ |
159 | __HYPERCALL_1ARG(a1); \ |
160 | asm volatile (__HYPERCALL \ |
161 | : __HYPERCALL_1PARAM \ |
162 | : __HYPERCALL_ENTRY(name) \ |
163 | : __HYPERCALL_CLOBBER1); \ |
164 | (type)__res; \ |
165 | }) |
166 | |
167 | #define _hypercall2(type, name, a1, a2) \ |
168 | ({ \ |
169 | __HYPERCALL_DECLS; \ |
170 | __HYPERCALL_2ARG(a1, a2); \ |
171 | asm volatile (__HYPERCALL \ |
172 | : __HYPERCALL_2PARAM \ |
173 | : __HYPERCALL_ENTRY(name) \ |
174 | : __HYPERCALL_CLOBBER2); \ |
175 | (type)__res; \ |
176 | }) |
177 | |
178 | #define _hypercall3(type, name, a1, a2, a3) \ |
179 | ({ \ |
180 | __HYPERCALL_DECLS; \ |
181 | __HYPERCALL_3ARG(a1, a2, a3); \ |
182 | asm volatile (__HYPERCALL \ |
183 | : __HYPERCALL_3PARAM \ |
184 | : __HYPERCALL_ENTRY(name) \ |
185 | : __HYPERCALL_CLOBBER3); \ |
186 | (type)__res; \ |
187 | }) |
188 | |
189 | #define _hypercall4(type, name, a1, a2, a3, a4) \ |
190 | ({ \ |
191 | __HYPERCALL_DECLS; \ |
192 | __HYPERCALL_4ARG(a1, a2, a3, a4); \ |
193 | asm volatile (__HYPERCALL \ |
194 | : __HYPERCALL_4PARAM \ |
195 | : __HYPERCALL_ENTRY(name) \ |
196 | : __HYPERCALL_CLOBBER4); \ |
197 | (type)__res; \ |
198 | }) |
199 | |
200 | static inline long |
201 | xen_single_call(unsigned int call, |
202 | unsigned long a1, unsigned long a2, |
203 | unsigned long a3, unsigned long a4, |
204 | unsigned long a5) |
205 | { |
206 | __HYPERCALL_DECLS; |
207 | __HYPERCALL_5ARG(a1, a2, a3, a4, a5); |
208 | |
209 | if (call >= PAGE_SIZE / sizeof(hypercall_page[0])) |
210 | return -EINVAL; |
211 | |
212 | asm volatile(CALL_NOSPEC |
213 | : __HYPERCALL_5PARAM |
214 | : [thunk_target] "a" (&hypercall_page[call]) |
215 | : __HYPERCALL_CLOBBER5); |
216 | |
217 | return (long)__res; |
218 | } |
219 | |
220 | static __always_inline void __xen_stac(void) |
221 | { |
222 | /* |
223 | * Suppress objtool seeing the STAC/CLAC and getting confused about it |
224 | * calling random code with AC=1. |
225 | */ |
226 | asm volatile(ANNOTATE_IGNORE_ALTERNATIVE |
227 | ASM_STAC ::: "memory" , "flags" ); |
228 | } |
229 | |
230 | static __always_inline void __xen_clac(void) |
231 | { |
232 | asm volatile(ANNOTATE_IGNORE_ALTERNATIVE |
233 | ASM_CLAC ::: "memory" , "flags" ); |
234 | } |
235 | |
236 | static inline long |
237 | privcmd_call(unsigned int call, |
238 | unsigned long a1, unsigned long a2, |
239 | unsigned long a3, unsigned long a4, |
240 | unsigned long a5) |
241 | { |
242 | long res; |
243 | |
244 | __xen_stac(); |
245 | res = xen_single_call(call, a1, a2, a3, a4, a5); |
246 | __xen_clac(); |
247 | |
248 | return res; |
249 | } |
250 | |
251 | #ifdef CONFIG_XEN_PV |
252 | static inline int |
253 | HYPERVISOR_set_trap_table(struct trap_info *table) |
254 | { |
255 | return _hypercall1(int, set_trap_table, table); |
256 | } |
257 | |
258 | static inline int |
259 | HYPERVISOR_mmu_update(struct mmu_update *req, int count, |
260 | int *success_count, domid_t domid) |
261 | { |
262 | return _hypercall4(int, mmu_update, req, count, success_count, domid); |
263 | } |
264 | |
265 | static inline int |
266 | HYPERVISOR_mmuext_op(struct mmuext_op *op, int count, |
267 | int *success_count, domid_t domid) |
268 | { |
269 | return _hypercall4(int, mmuext_op, op, count, success_count, domid); |
270 | } |
271 | |
272 | static inline int |
273 | HYPERVISOR_set_gdt(unsigned long *frame_list, int entries) |
274 | { |
275 | return _hypercall2(int, set_gdt, frame_list, entries); |
276 | } |
277 | |
278 | static inline int |
279 | HYPERVISOR_callback_op(int cmd, void *arg) |
280 | { |
281 | return _hypercall2(int, callback_op, cmd, arg); |
282 | } |
283 | |
284 | static __always_inline int |
285 | HYPERVISOR_set_debugreg(int reg, unsigned long value) |
286 | { |
287 | return _hypercall2(int, set_debugreg, reg, value); |
288 | } |
289 | |
290 | static __always_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 | return _hypercall2(int, update_descriptor, ma, desc); |
300 | } |
301 | |
302 | static inline int |
303 | HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val, |
304 | unsigned long flags) |
305 | { |
306 | return _hypercall3(int, update_va_mapping, va, new_val.pte, flags); |
307 | } |
308 | |
309 | static inline int |
310 | HYPERVISOR_set_segment_base(int reg, unsigned long value) |
311 | { |
312 | return _hypercall2(int, set_segment_base, reg, value); |
313 | } |
314 | |
315 | static inline void |
316 | MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set) |
317 | { |
318 | mcl->op = __HYPERVISOR_fpu_taskswitch; |
319 | mcl->args[0] = set; |
320 | |
321 | trace_xen_mc_entry(mc: mcl, nargs: 1); |
322 | } |
323 | |
324 | static inline void |
325 | MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va, |
326 | pte_t new_val, unsigned long flags) |
327 | { |
328 | mcl->op = __HYPERVISOR_update_va_mapping; |
329 | mcl->args[0] = va; |
330 | mcl->args[1] = new_val.pte; |
331 | mcl->args[2] = flags; |
332 | |
333 | trace_xen_mc_entry(mc: mcl, nargs: 3); |
334 | } |
335 | |
336 | static inline void |
337 | MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr, |
338 | struct desc_struct desc) |
339 | { |
340 | mcl->op = __HYPERVISOR_update_descriptor; |
341 | mcl->args[0] = maddr; |
342 | mcl->args[1] = *(unsigned long *)&desc; |
343 | |
344 | trace_xen_mc_entry(mc: mcl, nargs: 2); |
345 | } |
346 | |
347 | static inline void |
348 | MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req, |
349 | int count, int *success_count, domid_t domid) |
350 | { |
351 | mcl->op = __HYPERVISOR_mmu_update; |
352 | mcl->args[0] = (unsigned long)req; |
353 | mcl->args[1] = count; |
354 | mcl->args[2] = (unsigned long)success_count; |
355 | mcl->args[3] = domid; |
356 | |
357 | trace_xen_mc_entry(mc: mcl, nargs: 4); |
358 | } |
359 | |
360 | static inline void |
361 | MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count, |
362 | int *success_count, domid_t domid) |
363 | { |
364 | mcl->op = __HYPERVISOR_mmuext_op; |
365 | mcl->args[0] = (unsigned long)op; |
366 | mcl->args[1] = count; |
367 | mcl->args[2] = (unsigned long)success_count; |
368 | mcl->args[3] = domid; |
369 | |
370 | trace_xen_mc_entry(mc: mcl, nargs: 4); |
371 | } |
372 | |
373 | static inline void |
374 | MULTI_stack_switch(struct multicall_entry *mcl, |
375 | unsigned long ss, unsigned long esp) |
376 | { |
377 | mcl->op = __HYPERVISOR_stack_switch; |
378 | mcl->args[0] = ss; |
379 | mcl->args[1] = esp; |
380 | |
381 | trace_xen_mc_entry(mc: mcl, nargs: 2); |
382 | } |
383 | #endif |
384 | |
385 | static __always_inline int |
386 | HYPERVISOR_sched_op(int cmd, void *arg) |
387 | { |
388 | return _hypercall2(int, sched_op, cmd, arg); |
389 | } |
390 | |
391 | static inline long |
392 | HYPERVISOR_set_timer_op(u64 timeout) |
393 | { |
394 | unsigned long timeout_hi = (unsigned long)(timeout>>32); |
395 | unsigned long timeout_lo = (unsigned long)timeout; |
396 | return _hypercall2(long, set_timer_op, timeout_lo, timeout_hi); |
397 | } |
398 | |
399 | static inline int |
400 | HYPERVISOR_mca(struct xen_mc *mc_op) |
401 | { |
402 | mc_op->interface_version = XEN_MCA_INTERFACE_VERSION; |
403 | return _hypercall1(int, mca, mc_op); |
404 | } |
405 | |
406 | static inline int |
407 | HYPERVISOR_platform_op(struct xen_platform_op *op) |
408 | { |
409 | op->interface_version = XENPF_INTERFACE_VERSION; |
410 | return _hypercall1(int, platform_op, op); |
411 | } |
412 | |
413 | static inline long |
414 | HYPERVISOR_memory_op(unsigned int cmd, void *arg) |
415 | { |
416 | return _hypercall2(long, memory_op, cmd, arg); |
417 | } |
418 | |
419 | static inline int |
420 | HYPERVISOR_multicall(void *call_list, uint32_t nr_calls) |
421 | { |
422 | return _hypercall2(int, multicall, call_list, nr_calls); |
423 | } |
424 | |
425 | static inline int |
426 | HYPERVISOR_event_channel_op(int cmd, void *arg) |
427 | { |
428 | return _hypercall2(int, event_channel_op, cmd, arg); |
429 | } |
430 | |
431 | static __always_inline int |
432 | HYPERVISOR_xen_version(int cmd, void *arg) |
433 | { |
434 | return _hypercall2(int, xen_version, cmd, arg); |
435 | } |
436 | |
437 | static inline int |
438 | HYPERVISOR_console_io(int cmd, int count, char *str) |
439 | { |
440 | return _hypercall3(int, console_io, cmd, count, str); |
441 | } |
442 | |
443 | static inline int |
444 | HYPERVISOR_physdev_op(int cmd, void *arg) |
445 | { |
446 | return _hypercall2(int, physdev_op, cmd, arg); |
447 | } |
448 | |
449 | static inline int |
450 | HYPERVISOR_grant_table_op(unsigned int cmd, void *uop, unsigned int count) |
451 | { |
452 | return _hypercall3(int, grant_table_op, cmd, uop, count); |
453 | } |
454 | |
455 | static inline int |
456 | HYPERVISOR_vm_assist(unsigned int cmd, unsigned int type) |
457 | { |
458 | return _hypercall2(int, vm_assist, cmd, type); |
459 | } |
460 | |
461 | static inline int |
462 | HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *) |
463 | { |
464 | return _hypercall3(int, vcpu_op, cmd, vcpuid, extra_args); |
465 | } |
466 | |
467 | static inline int |
468 | HYPERVISOR_suspend(unsigned long start_info_mfn) |
469 | { |
470 | struct sched_shutdown r = { .reason = SHUTDOWN_suspend }; |
471 | |
472 | /* |
473 | * For a PV guest the tools require that the start_info mfn be |
474 | * present in rdx/edx when the hypercall is made. Per the |
475 | * hypercall calling convention this is the third hypercall |
476 | * argument, which is start_info_mfn here. |
477 | */ |
478 | return _hypercall3(int, sched_op, SCHEDOP_shutdown, &r, start_info_mfn); |
479 | } |
480 | |
481 | static inline unsigned long __must_check |
482 | HYPERVISOR_hvm_op(int op, void *arg) |
483 | { |
484 | return _hypercall2(unsigned long, hvm_op, op, arg); |
485 | } |
486 | |
487 | static inline int |
488 | HYPERVISOR_xenpmu_op(unsigned int op, void *arg) |
489 | { |
490 | return _hypercall2(int, xenpmu_op, op, arg); |
491 | } |
492 | |
493 | static inline int |
494 | HYPERVISOR_dm_op( |
495 | domid_t dom, unsigned int nr_bufs, struct xen_dm_op_buf *bufs) |
496 | { |
497 | int ret; |
498 | __xen_stac(); |
499 | ret = _hypercall3(int, dm_op, dom, nr_bufs, bufs); |
500 | __xen_clac(); |
501 | return ret; |
502 | } |
503 | |
504 | #endif /* _ASM_X86_XEN_HYPERCALL_H */ |
505 | |