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 #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 as 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 #define _hypercall5(type, name, a1, a2, a3, a4, a5) \ 201 ({ \ 202 __HYPERCALL_DECLS; \ 203 __HYPERCALL_5ARG(a1, a2, a3, a4, a5); \ 204 asm volatile (__HYPERCALL \ 205 : __HYPERCALL_5PARAM \ 206 : __HYPERCALL_ENTRY(name) \ 207 : __HYPERCALL_CLOBBER5); \ 208 (type)__res; \ 209 }) 210 211 static inline long 212 privcmd_call(unsigned call, 213 unsigned long a1, unsigned long a2, 214 unsigned long a3, unsigned long a4, 215 unsigned long a5) 216 { 217 __HYPERCALL_DECLS; 218 __HYPERCALL_5ARG(a1, a2, a3, a4, a5); 219 220 stac(); 221 asm volatile(CALL_NOSPEC 222 : __HYPERCALL_5PARAM 223 : [thunk_target] "a" (&hypercall_page[call]) 224 : __HYPERCALL_CLOBBER5); 225 clac(); 226 227 return (long)__res; 228 } 229 230 static inline int 231 HYPERVISOR_set_trap_table(struct trap_info *table) 232 { 233 return _hypercall1(int, set_trap_table, table); 234 } 235 236 static inline int 237 HYPERVISOR_mmu_update(struct mmu_update *req, int count, 238 int *success_count, domid_t domid) 239 { 240 return _hypercall4(int, mmu_update, req, count, success_count, domid); 241 } 242 243 static inline int 244 HYPERVISOR_mmuext_op(struct mmuext_op *op, int count, 245 int *success_count, domid_t domid) 246 { 247 return _hypercall4(int, mmuext_op, op, count, success_count, domid); 248 } 249 250 static inline int 251 HYPERVISOR_set_gdt(unsigned long *frame_list, int entries) 252 { 253 return _hypercall2(int, set_gdt, frame_list, entries); 254 } 255 256 static inline int 257 HYPERVISOR_stack_switch(unsigned long ss, unsigned long esp) 258 { 259 return _hypercall2(int, stack_switch, ss, esp); 260 } 261 262 #ifdef CONFIG_X86_32 263 static inline int 264 HYPERVISOR_set_callbacks(unsigned long event_selector, 265 unsigned long event_address, 266 unsigned long failsafe_selector, 267 unsigned long failsafe_address) 268 { 269 return _hypercall4(int, set_callbacks, 270 event_selector, event_address, 271 failsafe_selector, failsafe_address); 272 } 273 #else /* CONFIG_X86_64 */ 274 static inline int 275 HYPERVISOR_set_callbacks(unsigned long event_address, 276 unsigned long failsafe_address, 277 unsigned long syscall_address) 278 { 279 return _hypercall3(int, set_callbacks, 280 event_address, failsafe_address, 281 syscall_address); 282 } 283 #endif /* CONFIG_X86_{32,64} */ 284 285 static inline int 286 HYPERVISOR_callback_op(int cmd, void *arg) 287 { 288 return _hypercall2(int, callback_op, cmd, arg); 289 } 290 291 static inline int 292 HYPERVISOR_fpu_taskswitch(int set) 293 { 294 return _hypercall1(int, fpu_taskswitch, set); 295 } 296 297 static inline int 298 HYPERVISOR_sched_op(int cmd, void *arg) 299 { 300 return _hypercall2(int, sched_op, cmd, arg); 301 } 302 303 static inline long 304 HYPERVISOR_set_timer_op(u64 timeout) 305 { 306 unsigned long timeout_hi = (unsigned long)(timeout>>32); 307 unsigned long timeout_lo = (unsigned long)timeout; 308 return _hypercall2(long, set_timer_op, timeout_lo, timeout_hi); 309 } 310 311 static inline int 312 HYPERVISOR_mca(struct xen_mc *mc_op) 313 { 314 mc_op->interface_version = XEN_MCA_INTERFACE_VERSION; 315 return _hypercall1(int, mca, mc_op); 316 } 317 318 static inline int 319 HYPERVISOR_platform_op(struct xen_platform_op *op) 320 { 321 op->interface_version = XENPF_INTERFACE_VERSION; 322 return _hypercall1(int, platform_op, op); 323 } 324 325 static inline int 326 HYPERVISOR_set_debugreg(int reg, unsigned long value) 327 { 328 return _hypercall2(int, set_debugreg, reg, value); 329 } 330 331 static inline unsigned long 332 HYPERVISOR_get_debugreg(int reg) 333 { 334 return _hypercall1(unsigned long, get_debugreg, reg); 335 } 336 337 static inline int 338 HYPERVISOR_update_descriptor(u64 ma, u64 desc) 339 { 340 if (sizeof(u64) == sizeof(long)) 341 return _hypercall2(int, update_descriptor, ma, desc); 342 return _hypercall4(int, update_descriptor, ma, ma>>32, desc, desc>>32); 343 } 344 345 static inline long 346 HYPERVISOR_memory_op(unsigned int cmd, void *arg) 347 { 348 return _hypercall2(long, memory_op, cmd, arg); 349 } 350 351 static inline int 352 HYPERVISOR_multicall(void *call_list, uint32_t nr_calls) 353 { 354 return _hypercall2(int, multicall, call_list, nr_calls); 355 } 356 357 static inline int 358 HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val, 359 unsigned long flags) 360 { 361 if (sizeof(new_val) == sizeof(long)) 362 return _hypercall3(int, update_va_mapping, va, 363 new_val.pte, flags); 364 else 365 return _hypercall4(int, update_va_mapping, va, 366 new_val.pte, new_val.pte >> 32, flags); 367 } 368 extern int __must_check xen_event_channel_op_compat(int, void *); 369 370 static inline int 371 HYPERVISOR_event_channel_op(int cmd, void *arg) 372 { 373 int rc = _hypercall2(int, event_channel_op, cmd, arg); 374 if (unlikely(rc == -ENOSYS)) 375 rc = xen_event_channel_op_compat(cmd, arg); 376 return rc; 377 } 378 379 static inline int 380 HYPERVISOR_xen_version(int cmd, void *arg) 381 { 382 return _hypercall2(int, xen_version, cmd, arg); 383 } 384 385 static inline int 386 HYPERVISOR_console_io(int cmd, int count, char *str) 387 { 388 return _hypercall3(int, console_io, cmd, count, str); 389 } 390 391 extern int __must_check xen_physdev_op_compat(int, void *); 392 393 static inline int 394 HYPERVISOR_physdev_op(int cmd, void *arg) 395 { 396 int rc = _hypercall2(int, physdev_op, cmd, arg); 397 if (unlikely(rc == -ENOSYS)) 398 rc = xen_physdev_op_compat(cmd, arg); 399 return rc; 400 } 401 402 static inline int 403 HYPERVISOR_grant_table_op(unsigned int cmd, void *uop, unsigned int count) 404 { 405 return _hypercall3(int, grant_table_op, cmd, uop, count); 406 } 407 408 static inline int 409 HYPERVISOR_update_va_mapping_otherdomain(unsigned long va, pte_t new_val, 410 unsigned long flags, domid_t domid) 411 { 412 if (sizeof(new_val) == sizeof(long)) 413 return _hypercall4(int, update_va_mapping_otherdomain, va, 414 new_val.pte, flags, domid); 415 else 416 return _hypercall5(int, update_va_mapping_otherdomain, va, 417 new_val.pte, new_val.pte >> 32, 418 flags, domid); 419 } 420 421 static inline int 422 HYPERVISOR_vm_assist(unsigned int cmd, unsigned int type) 423 { 424 return _hypercall2(int, vm_assist, cmd, type); 425 } 426 427 static inline int 428 HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args) 429 { 430 return _hypercall3(int, vcpu_op, cmd, vcpuid, extra_args); 431 } 432 433 #ifdef CONFIG_X86_64 434 static inline int 435 HYPERVISOR_set_segment_base(int reg, unsigned long value) 436 { 437 return _hypercall2(int, set_segment_base, reg, value); 438 } 439 #endif 440 441 static inline int 442 HYPERVISOR_suspend(unsigned long start_info_mfn) 443 { 444 struct sched_shutdown r = { .reason = SHUTDOWN_suspend }; 445 446 /* 447 * For a PV guest the tools require that the start_info mfn be 448 * present in rdx/edx when the hypercall is made. Per the 449 * hypercall calling convention this is the third hypercall 450 * argument, which is start_info_mfn here. 451 */ 452 return _hypercall3(int, sched_op, SCHEDOP_shutdown, &r, start_info_mfn); 453 } 454 455 static inline int 456 HYPERVISOR_nmi_op(unsigned long op, unsigned long arg) 457 { 458 return _hypercall2(int, nmi_op, op, arg); 459 } 460 461 static inline unsigned long __must_check 462 HYPERVISOR_hvm_op(int op, void *arg) 463 { 464 return _hypercall2(unsigned long, hvm_op, op, arg); 465 } 466 467 static inline int 468 HYPERVISOR_tmem_op( 469 struct tmem_op *op) 470 { 471 return _hypercall1(int, tmem_op, op); 472 } 473 474 static inline int 475 HYPERVISOR_xenpmu_op(unsigned int op, void *arg) 476 { 477 return _hypercall2(int, xenpmu_op, op, arg); 478 } 479 480 static inline int 481 HYPERVISOR_dm_op( 482 domid_t dom, unsigned int nr_bufs, struct xen_dm_op_buf *bufs) 483 { 484 int ret; 485 stac(); 486 ret = _hypercall3(int, dm_op, dom, nr_bufs, bufs); 487 clac(); 488 return ret; 489 } 490 491 static inline void 492 MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set) 493 { 494 mcl->op = __HYPERVISOR_fpu_taskswitch; 495 mcl->args[0] = set; 496 497 trace_xen_mc_entry(mcl, 1); 498 } 499 500 static inline void 501 MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va, 502 pte_t new_val, unsigned long flags) 503 { 504 mcl->op = __HYPERVISOR_update_va_mapping; 505 mcl->args[0] = va; 506 if (sizeof(new_val) == sizeof(long)) { 507 mcl->args[1] = new_val.pte; 508 mcl->args[2] = flags; 509 } else { 510 mcl->args[1] = new_val.pte; 511 mcl->args[2] = new_val.pte >> 32; 512 mcl->args[3] = flags; 513 } 514 515 trace_xen_mc_entry(mcl, sizeof(new_val) == sizeof(long) ? 3 : 4); 516 } 517 518 static inline void 519 MULTI_grant_table_op(struct multicall_entry *mcl, unsigned int cmd, 520 void *uop, unsigned int count) 521 { 522 mcl->op = __HYPERVISOR_grant_table_op; 523 mcl->args[0] = cmd; 524 mcl->args[1] = (unsigned long)uop; 525 mcl->args[2] = count; 526 527 trace_xen_mc_entry(mcl, 3); 528 } 529 530 static inline void 531 MULTI_update_va_mapping_otherdomain(struct multicall_entry *mcl, unsigned long va, 532 pte_t new_val, unsigned long flags, 533 domid_t domid) 534 { 535 mcl->op = __HYPERVISOR_update_va_mapping_otherdomain; 536 mcl->args[0] = va; 537 if (sizeof(new_val) == sizeof(long)) { 538 mcl->args[1] = new_val.pte; 539 mcl->args[2] = flags; 540 mcl->args[3] = domid; 541 } else { 542 mcl->args[1] = new_val.pte; 543 mcl->args[2] = new_val.pte >> 32; 544 mcl->args[3] = flags; 545 mcl->args[4] = domid; 546 } 547 548 trace_xen_mc_entry(mcl, sizeof(new_val) == sizeof(long) ? 4 : 5); 549 } 550 551 static inline void 552 MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr, 553 struct desc_struct desc) 554 { 555 mcl->op = __HYPERVISOR_update_descriptor; 556 if (sizeof(maddr) == sizeof(long)) { 557 mcl->args[0] = maddr; 558 mcl->args[1] = *(unsigned long *)&desc; 559 } else { 560 u32 *p = (u32 *)&desc; 561 562 mcl->args[0] = maddr; 563 mcl->args[1] = maddr >> 32; 564 mcl->args[2] = *p++; 565 mcl->args[3] = *p; 566 } 567 568 trace_xen_mc_entry(mcl, sizeof(maddr) == sizeof(long) ? 2 : 4); 569 } 570 571 static inline void 572 MULTI_memory_op(struct multicall_entry *mcl, unsigned int cmd, void *arg) 573 { 574 mcl->op = __HYPERVISOR_memory_op; 575 mcl->args[0] = cmd; 576 mcl->args[1] = (unsigned long)arg; 577 578 trace_xen_mc_entry(mcl, 2); 579 } 580 581 static inline void 582 MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req, 583 int count, int *success_count, domid_t domid) 584 { 585 mcl->op = __HYPERVISOR_mmu_update; 586 mcl->args[0] = (unsigned long)req; 587 mcl->args[1] = count; 588 mcl->args[2] = (unsigned long)success_count; 589 mcl->args[3] = domid; 590 591 trace_xen_mc_entry(mcl, 4); 592 } 593 594 static inline void 595 MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count, 596 int *success_count, domid_t domid) 597 { 598 mcl->op = __HYPERVISOR_mmuext_op; 599 mcl->args[0] = (unsigned long)op; 600 mcl->args[1] = count; 601 mcl->args[2] = (unsigned long)success_count; 602 mcl->args[3] = domid; 603 604 trace_xen_mc_entry(mcl, 4); 605 } 606 607 static inline void 608 MULTI_set_gdt(struct multicall_entry *mcl, unsigned long *frames, int entries) 609 { 610 mcl->op = __HYPERVISOR_set_gdt; 611 mcl->args[0] = (unsigned long)frames; 612 mcl->args[1] = entries; 613 614 trace_xen_mc_entry(mcl, 2); 615 } 616 617 static inline void 618 MULTI_stack_switch(struct multicall_entry *mcl, 619 unsigned long ss, unsigned long esp) 620 { 621 mcl->op = __HYPERVISOR_stack_switch; 622 mcl->args[0] = ss; 623 mcl->args[1] = esp; 624 625 trace_xen_mc_entry(mcl, 2); 626 } 627 628 #endif /* _ASM_X86_XEN_HYPERCALL_H */ 629