arch/x86/include/asm/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 _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 */