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 52 /* 53 * The hypercall asms have to meet several constraints: 54 * - Work on 32- and 64-bit. 55 * The two architectures put their arguments in different sets of 56 * registers. 57 * 58 * - Work around asm syntax quirks 59 * It isn't possible to specify one of the rNN registers in a 60 * constraint, so we use explicit register variables to get the 61 * args into the right place. 62 * 63 * - Mark all registers as potentially clobbered 64 * Even unused parameters can be clobbered by the hypervisor, so we 65 * need to make sure gcc knows it. 66 * 67 * - Avoid compiler bugs. 68 * This is the tricky part. Because x86_32 has such a constrained 69 * register set, gcc versions below 4.3 have trouble generating 70 * code when all the arg registers and memory are trashed by the 71 * asm. There are syntactically simpler ways of achieving the 72 * semantics below, but they cause the compiler to crash. 73 * 74 * The only combination I found which works is: 75 * - assign the __argX variables first 76 * - list all actually used parameters as "+r" (__argX) 77 * - clobber the rest 78 * 79 * The result certainly isn't pretty, and it really shows up cpp's 80 * weakness as as macro language. Sorry. (But let's just give thanks 81 * there aren't more than 5 arguments...) 82 */ 83 84 extern struct { char _entry[32]; } hypercall_page[]; 85 86 #define __HYPERCALL "call hypercall_page+%c[offset]" 87 #define __HYPERCALL_ENTRY(x) \ 88 [offset] "i" (__HYPERVISOR_##x * sizeof(hypercall_page[0])) 89 90 #ifdef CONFIG_X86_32 91 #define __HYPERCALL_RETREG "eax" 92 #define __HYPERCALL_ARG1REG "ebx" 93 #define __HYPERCALL_ARG2REG "ecx" 94 #define __HYPERCALL_ARG3REG "edx" 95 #define __HYPERCALL_ARG4REG "esi" 96 #define __HYPERCALL_ARG5REG "edi" 97 #else 98 #define __HYPERCALL_RETREG "rax" 99 #define __HYPERCALL_ARG1REG "rdi" 100 #define __HYPERCALL_ARG2REG "rsi" 101 #define __HYPERCALL_ARG3REG "rdx" 102 #define __HYPERCALL_ARG4REG "r10" 103 #define __HYPERCALL_ARG5REG "r8" 104 #endif 105 106 #define __HYPERCALL_DECLS \ 107 register unsigned long __res asm(__HYPERCALL_RETREG); \ 108 register unsigned long __arg1 asm(__HYPERCALL_ARG1REG) = __arg1; \ 109 register unsigned long __arg2 asm(__HYPERCALL_ARG2REG) = __arg2; \ 110 register unsigned long __arg3 asm(__HYPERCALL_ARG3REG) = __arg3; \ 111 register unsigned long __arg4 asm(__HYPERCALL_ARG4REG) = __arg4; \ 112 register unsigned long __arg5 asm(__HYPERCALL_ARG5REG) = __arg5; 113 114 #define __HYPERCALL_0PARAM "=r" (__res) 115 #define __HYPERCALL_1PARAM __HYPERCALL_0PARAM, "+r" (__arg1) 116 #define __HYPERCALL_2PARAM __HYPERCALL_1PARAM, "+r" (__arg2) 117 #define __HYPERCALL_3PARAM __HYPERCALL_2PARAM, "+r" (__arg3) 118 #define __HYPERCALL_4PARAM __HYPERCALL_3PARAM, "+r" (__arg4) 119 #define __HYPERCALL_5PARAM __HYPERCALL_4PARAM, "+r" (__arg5) 120 121 #define __HYPERCALL_0ARG() 122 #define __HYPERCALL_1ARG(a1) \ 123 __HYPERCALL_0ARG() __arg1 = (unsigned long)(a1); 124 #define __HYPERCALL_2ARG(a1,a2) \ 125 __HYPERCALL_1ARG(a1) __arg2 = (unsigned long)(a2); 126 #define __HYPERCALL_3ARG(a1,a2,a3) \ 127 __HYPERCALL_2ARG(a1,a2) __arg3 = (unsigned long)(a3); 128 #define __HYPERCALL_4ARG(a1,a2,a3,a4) \ 129 __HYPERCALL_3ARG(a1,a2,a3) __arg4 = (unsigned long)(a4); 130 #define __HYPERCALL_5ARG(a1,a2,a3,a4,a5) \ 131 __HYPERCALL_4ARG(a1,a2,a3,a4) __arg5 = (unsigned long)(a5); 132 133 #define __HYPERCALL_CLOBBER5 "memory" 134 #define __HYPERCALL_CLOBBER4 __HYPERCALL_CLOBBER5, __HYPERCALL_ARG5REG 135 #define __HYPERCALL_CLOBBER3 __HYPERCALL_CLOBBER4, __HYPERCALL_ARG4REG 136 #define __HYPERCALL_CLOBBER2 __HYPERCALL_CLOBBER3, __HYPERCALL_ARG3REG 137 #define __HYPERCALL_CLOBBER1 __HYPERCALL_CLOBBER2, __HYPERCALL_ARG2REG 138 #define __HYPERCALL_CLOBBER0 __HYPERCALL_CLOBBER1, __HYPERCALL_ARG1REG 139 140 #define _hypercall0(type, name) \ 141 ({ \ 142 __HYPERCALL_DECLS; \ 143 __HYPERCALL_0ARG(); \ 144 asm volatile (__HYPERCALL \ 145 : __HYPERCALL_0PARAM \ 146 : __HYPERCALL_ENTRY(name) \ 147 : __HYPERCALL_CLOBBER0); \ 148 (type)__res; \ 149 }) 150 151 #define _hypercall1(type, name, a1) \ 152 ({ \ 153 __HYPERCALL_DECLS; \ 154 __HYPERCALL_1ARG(a1); \ 155 asm volatile (__HYPERCALL \ 156 : __HYPERCALL_1PARAM \ 157 : __HYPERCALL_ENTRY(name) \ 158 : __HYPERCALL_CLOBBER1); \ 159 (type)__res; \ 160 }) 161 162 #define _hypercall2(type, name, a1, a2) \ 163 ({ \ 164 __HYPERCALL_DECLS; \ 165 __HYPERCALL_2ARG(a1, a2); \ 166 asm volatile (__HYPERCALL \ 167 : __HYPERCALL_2PARAM \ 168 : __HYPERCALL_ENTRY(name) \ 169 : __HYPERCALL_CLOBBER2); \ 170 (type)__res; \ 171 }) 172 173 #define _hypercall3(type, name, a1, a2, a3) \ 174 ({ \ 175 __HYPERCALL_DECLS; \ 176 __HYPERCALL_3ARG(a1, a2, a3); \ 177 asm volatile (__HYPERCALL \ 178 : __HYPERCALL_3PARAM \ 179 : __HYPERCALL_ENTRY(name) \ 180 : __HYPERCALL_CLOBBER3); \ 181 (type)__res; \ 182 }) 183 184 #define _hypercall4(type, name, a1, a2, a3, a4) \ 185 ({ \ 186 __HYPERCALL_DECLS; \ 187 __HYPERCALL_4ARG(a1, a2, a3, a4); \ 188 asm volatile (__HYPERCALL \ 189 : __HYPERCALL_4PARAM \ 190 : __HYPERCALL_ENTRY(name) \ 191 : __HYPERCALL_CLOBBER4); \ 192 (type)__res; \ 193 }) 194 195 #define _hypercall5(type, name, a1, a2, a3, a4, a5) \ 196 ({ \ 197 __HYPERCALL_DECLS; \ 198 __HYPERCALL_5ARG(a1, a2, a3, a4, a5); \ 199 asm volatile (__HYPERCALL \ 200 : __HYPERCALL_5PARAM \ 201 : __HYPERCALL_ENTRY(name) \ 202 : __HYPERCALL_CLOBBER5); \ 203 (type)__res; \ 204 }) 205 206 static inline long 207 privcmd_call(unsigned call, 208 unsigned long a1, unsigned long a2, 209 unsigned long a3, unsigned long a4, 210 unsigned long a5) 211 { 212 __HYPERCALL_DECLS; 213 __HYPERCALL_5ARG(a1, a2, a3, a4, a5); 214 215 asm volatile("call *%[call]" 216 : __HYPERCALL_5PARAM 217 : [call] "a" (&hypercall_page[call]) 218 : __HYPERCALL_CLOBBER5); 219 220 return (long)__res; 221 } 222 223 static inline int 224 HYPERVISOR_set_trap_table(struct trap_info *table) 225 { 226 return _hypercall1(int, set_trap_table, table); 227 } 228 229 static inline int 230 HYPERVISOR_mmu_update(struct mmu_update *req, int count, 231 int *success_count, domid_t domid) 232 { 233 return _hypercall4(int, mmu_update, req, count, success_count, domid); 234 } 235 236 static inline int 237 HYPERVISOR_mmuext_op(struct mmuext_op *op, int count, 238 int *success_count, domid_t domid) 239 { 240 return _hypercall4(int, mmuext_op, op, count, success_count, domid); 241 } 242 243 static inline int 244 HYPERVISOR_set_gdt(unsigned long *frame_list, int entries) 245 { 246 return _hypercall2(int, set_gdt, frame_list, entries); 247 } 248 249 static inline int 250 HYPERVISOR_stack_switch(unsigned long ss, unsigned long esp) 251 { 252 return _hypercall2(int, stack_switch, ss, esp); 253 } 254 255 #ifdef CONFIG_X86_32 256 static inline int 257 HYPERVISOR_set_callbacks(unsigned long event_selector, 258 unsigned long event_address, 259 unsigned long failsafe_selector, 260 unsigned long failsafe_address) 261 { 262 return _hypercall4(int, set_callbacks, 263 event_selector, event_address, 264 failsafe_selector, failsafe_address); 265 } 266 #else /* CONFIG_X86_64 */ 267 static inline int 268 HYPERVISOR_set_callbacks(unsigned long event_address, 269 unsigned long failsafe_address, 270 unsigned long syscall_address) 271 { 272 return _hypercall3(int, set_callbacks, 273 event_address, failsafe_address, 274 syscall_address); 275 } 276 #endif /* CONFIG_X86_{32,64} */ 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 inline int 285 HYPERVISOR_fpu_taskswitch(int set) 286 { 287 return _hypercall1(int, fpu_taskswitch, set); 288 } 289 290 static inline int 291 HYPERVISOR_sched_op(int cmd, void *arg) 292 { 293 return _hypercall2(int, sched_op, cmd, arg); 294 } 295 296 static inline long 297 HYPERVISOR_set_timer_op(u64 timeout) 298 { 299 unsigned long timeout_hi = (unsigned long)(timeout>>32); 300 unsigned long timeout_lo = (unsigned long)timeout; 301 return _hypercall2(long, set_timer_op, timeout_lo, timeout_hi); 302 } 303 304 static inline int 305 HYPERVISOR_dom0_op(struct xen_platform_op *platform_op) 306 { 307 platform_op->interface_version = XENPF_INTERFACE_VERSION; 308 return _hypercall1(int, dom0_op, platform_op); 309 } 310 311 static inline int 312 HYPERVISOR_set_debugreg(int reg, unsigned long value) 313 { 314 return _hypercall2(int, set_debugreg, reg, value); 315 } 316 317 static inline unsigned long 318 HYPERVISOR_get_debugreg(int reg) 319 { 320 return _hypercall1(unsigned long, get_debugreg, reg); 321 } 322 323 static inline int 324 HYPERVISOR_update_descriptor(u64 ma, u64 desc) 325 { 326 if (sizeof(u64) == sizeof(long)) 327 return _hypercall2(int, update_descriptor, ma, desc); 328 return _hypercall4(int, update_descriptor, ma, ma>>32, desc, desc>>32); 329 } 330 331 static inline int 332 HYPERVISOR_memory_op(unsigned int cmd, void *arg) 333 { 334 return _hypercall2(int, memory_op, cmd, arg); 335 } 336 337 static inline int 338 HYPERVISOR_multicall(void *call_list, int nr_calls) 339 { 340 return _hypercall2(int, multicall, call_list, nr_calls); 341 } 342 343 static inline int 344 HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val, 345 unsigned long flags) 346 { 347 if (sizeof(new_val) == sizeof(long)) 348 return _hypercall3(int, update_va_mapping, va, 349 new_val.pte, flags); 350 else 351 return _hypercall4(int, update_va_mapping, va, 352 new_val.pte, new_val.pte >> 32, flags); 353 } 354 355 static inline int 356 HYPERVISOR_event_channel_op(int cmd, void *arg) 357 { 358 int rc = _hypercall2(int, event_channel_op, cmd, arg); 359 if (unlikely(rc == -ENOSYS)) { 360 struct evtchn_op op; 361 op.cmd = cmd; 362 memcpy(&op.u, arg, sizeof(op.u)); 363 rc = _hypercall1(int, event_channel_op_compat, &op); 364 memcpy(arg, &op.u, sizeof(op.u)); 365 } 366 return rc; 367 } 368 369 static inline int 370 HYPERVISOR_xen_version(int cmd, void *arg) 371 { 372 return _hypercall2(int, xen_version, cmd, arg); 373 } 374 375 static inline int 376 HYPERVISOR_console_io(int cmd, int count, char *str) 377 { 378 return _hypercall3(int, console_io, cmd, count, str); 379 } 380 381 static inline int 382 HYPERVISOR_physdev_op(int cmd, void *arg) 383 { 384 int rc = _hypercall2(int, physdev_op, cmd, arg); 385 if (unlikely(rc == -ENOSYS)) { 386 struct physdev_op op; 387 op.cmd = cmd; 388 memcpy(&op.u, arg, sizeof(op.u)); 389 rc = _hypercall1(int, physdev_op_compat, &op); 390 memcpy(arg, &op.u, sizeof(op.u)); 391 } 392 return rc; 393 } 394 395 static inline int 396 HYPERVISOR_grant_table_op(unsigned int cmd, void *uop, unsigned int count) 397 { 398 return _hypercall3(int, grant_table_op, cmd, uop, count); 399 } 400 401 static inline int 402 HYPERVISOR_update_va_mapping_otherdomain(unsigned long va, pte_t new_val, 403 unsigned long flags, domid_t domid) 404 { 405 if (sizeof(new_val) == sizeof(long)) 406 return _hypercall4(int, update_va_mapping_otherdomain, va, 407 new_val.pte, flags, domid); 408 else 409 return _hypercall5(int, update_va_mapping_otherdomain, va, 410 new_val.pte, new_val.pte >> 32, 411 flags, domid); 412 } 413 414 static inline int 415 HYPERVISOR_vm_assist(unsigned int cmd, unsigned int type) 416 { 417 return _hypercall2(int, vm_assist, cmd, type); 418 } 419 420 static inline int 421 HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args) 422 { 423 return _hypercall3(int, vcpu_op, cmd, vcpuid, extra_args); 424 } 425 426 #ifdef CONFIG_X86_64 427 static inline int 428 HYPERVISOR_set_segment_base(int reg, unsigned long value) 429 { 430 return _hypercall2(int, set_segment_base, reg, value); 431 } 432 #endif 433 434 static inline int 435 HYPERVISOR_suspend(unsigned long start_info_mfn) 436 { 437 struct sched_shutdown r = { .reason = SHUTDOWN_suspend }; 438 439 /* 440 * For a PV guest the tools require that the start_info mfn be 441 * present in rdx/edx when the hypercall is made. Per the 442 * hypercall calling convention this is the third hypercall 443 * argument, which is start_info_mfn here. 444 */ 445 return _hypercall3(int, sched_op, SCHEDOP_shutdown, &r, start_info_mfn); 446 } 447 448 static inline int 449 HYPERVISOR_nmi_op(unsigned long op, unsigned long arg) 450 { 451 return _hypercall2(int, nmi_op, op, arg); 452 } 453 454 static inline unsigned long __must_check 455 HYPERVISOR_hvm_op(int op, void *arg) 456 { 457 return _hypercall2(unsigned long, hvm_op, op, arg); 458 } 459 460 static inline int 461 HYPERVISOR_tmem_op( 462 struct tmem_op *op) 463 { 464 return _hypercall1(int, tmem_op, op); 465 } 466 467 static inline void 468 MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set) 469 { 470 mcl->op = __HYPERVISOR_fpu_taskswitch; 471 mcl->args[0] = set; 472 473 trace_xen_mc_entry(mcl, 1); 474 } 475 476 static inline void 477 MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va, 478 pte_t new_val, unsigned long flags) 479 { 480 mcl->op = __HYPERVISOR_update_va_mapping; 481 mcl->args[0] = va; 482 if (sizeof(new_val) == sizeof(long)) { 483 mcl->args[1] = new_val.pte; 484 mcl->args[2] = flags; 485 } else { 486 mcl->args[1] = new_val.pte; 487 mcl->args[2] = new_val.pte >> 32; 488 mcl->args[3] = flags; 489 } 490 491 trace_xen_mc_entry(mcl, sizeof(new_val) == sizeof(long) ? 3 : 4); 492 } 493 494 static inline void 495 MULTI_grant_table_op(struct multicall_entry *mcl, unsigned int cmd, 496 void *uop, unsigned int count) 497 { 498 mcl->op = __HYPERVISOR_grant_table_op; 499 mcl->args[0] = cmd; 500 mcl->args[1] = (unsigned long)uop; 501 mcl->args[2] = count; 502 503 trace_xen_mc_entry(mcl, 3); 504 } 505 506 static inline void 507 MULTI_update_va_mapping_otherdomain(struct multicall_entry *mcl, unsigned long va, 508 pte_t new_val, unsigned long flags, 509 domid_t domid) 510 { 511 mcl->op = __HYPERVISOR_update_va_mapping_otherdomain; 512 mcl->args[0] = va; 513 if (sizeof(new_val) == sizeof(long)) { 514 mcl->args[1] = new_val.pte; 515 mcl->args[2] = flags; 516 mcl->args[3] = domid; 517 } else { 518 mcl->args[1] = new_val.pte; 519 mcl->args[2] = new_val.pte >> 32; 520 mcl->args[3] = flags; 521 mcl->args[4] = domid; 522 } 523 524 trace_xen_mc_entry(mcl, sizeof(new_val) == sizeof(long) ? 4 : 5); 525 } 526 527 static inline void 528 MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr, 529 struct desc_struct desc) 530 { 531 mcl->op = __HYPERVISOR_update_descriptor; 532 if (sizeof(maddr) == sizeof(long)) { 533 mcl->args[0] = maddr; 534 mcl->args[1] = *(unsigned long *)&desc; 535 } else { 536 mcl->args[0] = maddr; 537 mcl->args[1] = maddr >> 32; 538 mcl->args[2] = desc.a; 539 mcl->args[3] = desc.b; 540 } 541 542 trace_xen_mc_entry(mcl, sizeof(maddr) == sizeof(long) ? 2 : 4); 543 } 544 545 static inline void 546 MULTI_memory_op(struct multicall_entry *mcl, unsigned int cmd, void *arg) 547 { 548 mcl->op = __HYPERVISOR_memory_op; 549 mcl->args[0] = cmd; 550 mcl->args[1] = (unsigned long)arg; 551 552 trace_xen_mc_entry(mcl, 2); 553 } 554 555 static inline void 556 MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req, 557 int count, int *success_count, domid_t domid) 558 { 559 mcl->op = __HYPERVISOR_mmu_update; 560 mcl->args[0] = (unsigned long)req; 561 mcl->args[1] = count; 562 mcl->args[2] = (unsigned long)success_count; 563 mcl->args[3] = domid; 564 565 trace_xen_mc_entry(mcl, 4); 566 } 567 568 static inline void 569 MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count, 570 int *success_count, domid_t domid) 571 { 572 mcl->op = __HYPERVISOR_mmuext_op; 573 mcl->args[0] = (unsigned long)op; 574 mcl->args[1] = count; 575 mcl->args[2] = (unsigned long)success_count; 576 mcl->args[3] = domid; 577 578 trace_xen_mc_entry(mcl, 4); 579 } 580 581 static inline void 582 MULTI_set_gdt(struct multicall_entry *mcl, unsigned long *frames, int entries) 583 { 584 mcl->op = __HYPERVISOR_set_gdt; 585 mcl->args[0] = (unsigned long)frames; 586 mcl->args[1] = entries; 587 588 trace_xen_mc_entry(mcl, 2); 589 } 590 591 static inline void 592 MULTI_stack_switch(struct multicall_entry *mcl, 593 unsigned long ss, unsigned long esp) 594 { 595 mcl->op = __HYPERVISOR_stack_switch; 596 mcl->args[0] = ss; 597 mcl->args[1] = esp; 598 599 trace_xen_mc_entry(mcl, 2); 600 } 601 602 #endif /* _ASM_X86_XEN_HYPERCALL_H */ 603