include/asm-x86/xen/hypercall.h

   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 __HYPERCALL_H__
  34 #define __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 static inline int
 230 HYPERVISOR_set_callbacks(unsigned long event_selector,
 231                          unsigned long event_address,
 232                          unsigned long failsafe_selector,
 233                          unsigned long failsafe_address)
 234 {
 235         return _hypercall4(int, set_callbacks,
 236                            event_selector, event_address,
 237                            failsafe_selector, failsafe_address);
 238 }
 239
 240 static inline int
 241 HYPERVISOR_callback_op(int cmd, void *arg)
 242 {
 243         return _hypercall2(int, callback_op, cmd, arg);
 244 }
 245
 246 static inline int
 247 HYPERVISOR_fpu_taskswitch(int set)
 248 {
 249         return _hypercall1(int, fpu_taskswitch, set);
 250 }
 251
 252 static inline int
 253 HYPERVISOR_sched_op(int cmd, void *arg)
 254 {
 255         return _hypercall2(int, sched_op_new, cmd, arg);
 256 }
 257
 258 static inline long
 259 HYPERVISOR_set_timer_op(u64 timeout)
 260 {
 261         unsigned long timeout_hi = (unsigned long)(timeout>>32);
 262         unsigned long timeout_lo = (unsigned long)timeout;
 263         return _hypercall2(long, set_timer_op, timeout_lo, timeout_hi);
 264 }
 265
 266 static inline int
 267 HYPERVISOR_set_debugreg(int reg, unsigned long value)
 268 {
 269         return _hypercall2(int, set_debugreg, reg, value);
 270 }
 271
 272 static inline unsigned long
 273 HYPERVISOR_get_debugreg(int reg)
 274 {
 275         return _hypercall1(unsigned long, get_debugreg, reg);
 276 }
 277
 278 static inline int
 279 HYPERVISOR_update_descriptor(u64 ma, u64 desc)
 280 {
 281         return _hypercall4(int, update_descriptor, ma, ma>>32, desc, desc>>32);
 282 }
 283
 284 static inline int
 285 HYPERVISOR_memory_op(unsigned int cmd, void *arg)
 286 {
 287         return _hypercall2(int, memory_op, cmd, arg);
 288 }
 289
 290 static inline int
 291 HYPERVISOR_multicall(void *call_list, int nr_calls)
 292 {
 293         return _hypercall2(int, multicall, call_list, nr_calls);
 294 }
 295
 296 static inline int
 297 HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val,
 298                              unsigned long flags)
 299 {
 300         if (sizeof(new_val) == sizeof(long))
 301                 return _hypercall3(int, update_va_mapping, va,
 302                                    new_val.pte, flags);
 303         else
 304                 return _hypercall4(int, update_va_mapping, va,
 305                                    new_val.pte, new_val.pte >> 32, flags);
 306 }
 307
 308 static inline int
 309 HYPERVISOR_event_channel_op(int cmd, void *arg)
 310 {
 311         int rc = _hypercall2(int, event_channel_op, cmd, arg);
 312         if (unlikely(rc == -ENOSYS)) {
 313                 struct evtchn_op op;
 314                 op.cmd = cmd;
 315                 memcpy(&op.u, arg, sizeof(op.u));
 316                 rc = _hypercall1(int, event_channel_op_compat, &op);
 317                 memcpy(arg, &op.u, sizeof(op.u));
 318         }
 319         return rc;
 320 }
 321
 322 static inline int
 323 HYPERVISOR_xen_version(int cmd, void *arg)
 324 {
 325         return _hypercall2(int, xen_version, cmd, arg);
 326 }
 327
 328 static inline int
 329 HYPERVISOR_console_io(int cmd, int count, char *str)
 330 {
 331         return _hypercall3(int, console_io, cmd, count, str);
 332 }
 333
 334 static inline int
 335 HYPERVISOR_physdev_op(int cmd, void *arg)
 336 {
 337         int rc = _hypercall2(int, physdev_op, cmd, arg);
 338         if (unlikely(rc == -ENOSYS)) {
 339                 struct physdev_op op;
 340                 op.cmd = cmd;
 341                 memcpy(&op.u, arg, sizeof(op.u));
 342                 rc = _hypercall1(int, physdev_op_compat, &op);
 343                 memcpy(arg, &op.u, sizeof(op.u));
 344         }
 345         return rc;
 346 }
 347
 348 static inline int
 349 HYPERVISOR_grant_table_op(unsigned int cmd, void *uop, unsigned int count)
 350 {
 351         return _hypercall3(int, grant_table_op, cmd, uop, count);
 352 }
 353
 354 static inline int
 355 HYPERVISOR_update_va_mapping_otherdomain(unsigned long va, pte_t new_val,
 356                                          unsigned long flags, domid_t domid)
 357 {
 358         if (sizeof(new_val) == sizeof(long))
 359                 return _hypercall4(int, update_va_mapping_otherdomain, va,
 360                                    new_val.pte, flags, domid);
 361         else
 362                 return _hypercall5(int, update_va_mapping_otherdomain, va,
 363                                    new_val.pte, new_val.pte >> 32,
 364                                    flags, domid);
 365 }
 366
 367 static inline int
 368 HYPERVISOR_vm_assist(unsigned int cmd, unsigned int type)
 369 {
 370         return _hypercall2(int, vm_assist, cmd, type);
 371 }
 372
 373 static inline int
 374 HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args)
 375 {
 376         return _hypercall3(int, vcpu_op, cmd, vcpuid, extra_args);
 377 }
 378
 379 static inline int
 380 HYPERVISOR_suspend(unsigned long srec)
 381 {
 382         return _hypercall3(int, sched_op, SCHEDOP_shutdown,
 383                            SHUTDOWN_suspend, srec);
 384 }
 385
 386 static inline int
 387 HYPERVISOR_nmi_op(unsigned long op, unsigned long arg)
 388 {
 389         return _hypercall2(int, nmi_op, op, arg);
 390 }
 391
 392 static inline void
 393 MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set)
 394 {
 395         mcl->op = __HYPERVISOR_fpu_taskswitch;
 396         mcl->args[0] = set;
 397 }
 398
 399 static inline void
 400 MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va,
 401                         pte_t new_val, unsigned long flags)
 402 {
 403         mcl->op = __HYPERVISOR_update_va_mapping;
 404         mcl->args[0] = va;
 405         if (sizeof(new_val) == sizeof(long)) {
 406                 mcl->args[1] = new_val.pte;
 407                 mcl->args[2] = flags;
 408         } else {
 409                 mcl->args[1] = new_val.pte;
 410                 mcl->args[2] = new_val.pte >> 32;
 411                 mcl->args[3] = flags;
 412         }
 413 }
 414
 415 static inline void
 416 MULTI_grant_table_op(struct multicall_entry *mcl, unsigned int cmd,
 417                      void *uop, unsigned int count)
 418 {
 419         mcl->op = __HYPERVISOR_grant_table_op;
 420         mcl->args[0] = cmd;
 421         mcl->args[1] = (unsigned long)uop;
 422         mcl->args[2] = count;
 423 }
 424
 425 static inline void
 426 MULTI_update_va_mapping_otherdomain(struct multicall_entry *mcl, unsigned long va,
 427                                     pte_t new_val, unsigned long flags,
 428                                     domid_t domid)
 429 {
 430         mcl->op = __HYPERVISOR_update_va_mapping_otherdomain;
 431         mcl->args[0] = va;
 432         if (sizeof(new_val) == sizeof(long)) {
 433                 mcl->args[1] = new_val.pte;
 434                 mcl->args[2] = flags;
 435                 mcl->args[3] = domid;
 436         } else {
 437                 mcl->args[1] = new_val.pte;
 438                 mcl->args[2] = new_val.pte >> 32;
 439                 mcl->args[3] = flags;
 440                 mcl->args[4] = domid;
 441         }
 442 }
 443
 444 static inline void
 445 MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr,
 446                         struct desc_struct desc)
 447 {
 448         mcl->op = __HYPERVISOR_update_descriptor;
 449         mcl->args[0] = maddr;
 450         mcl->args[1] = maddr >> 32;
 451         mcl->args[2] = desc.a;
 452         mcl->args[3] = desc.b;
 453 }
 454
 455 static inline void
 456 MULTI_memory_op(struct multicall_entry *mcl, unsigned int cmd, void *arg)
 457 {
 458         mcl->op = __HYPERVISOR_memory_op;
 459         mcl->args[0] = cmd;
 460         mcl->args[1] = (unsigned long)arg;
 461 }
 462
 463 static inline void
 464 MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req,
 465                  int count, int *success_count, domid_t domid)
 466 {
 467         mcl->op = __HYPERVISOR_mmu_update;
 468         mcl->args[0] = (unsigned long)req;
 469         mcl->args[1] = count;
 470         mcl->args[2] = (unsigned long)success_count;
 471         mcl->args[3] = domid;
 472 }
 473
 474 static inline void
 475 MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count,
 476                 int *success_count, domid_t domid)
 477 {
 478         mcl->op = __HYPERVISOR_mmuext_op;
 479         mcl->args[0] = (unsigned long)op;
 480         mcl->args[1] = count;
 481         mcl->args[2] = (unsigned long)success_count;
 482         mcl->args[3] = domid;
 483 }
 484
 485 static inline void
 486 MULTI_set_gdt(struct multicall_entry *mcl, unsigned long *frames, int entries)
 487 {
 488         mcl->op = __HYPERVISOR_set_gdt;
 489         mcl->args[0] = (unsigned long)frames;
 490         mcl->args[1] = entries;
 491 }
 492
 493 static inline void
 494 MULTI_stack_switch(struct multicall_entry *mcl,
 495                    unsigned long ss, unsigned long esp)
 496 {
 497         mcl->op = __HYPERVISOR_stack_switch;
 498         mcl->args[0] = ss;
 499         mcl->args[1] = esp;
 500 }
 501
 502 #endif /* __HYPERCALL_H__ */