palacios/src/palacios/vmm_sym_iface.c

   1 /*
   2  * This file is part of the Palacios Virtual Machine Monitor developed
   3  * by the V3VEE Project with funding from the United States National
   4  * Science Foundation and the Department of Energy.
   5  *
   6  * The V3VEE Project is a joint project between Northwestern University
   7  * and the University of New Mexico.  You can find out more at
   8  * http://www.v3vee.org
   9  *
  10  * Copyright (c) 2008, Jack Lange <jarusl@cs.northwestern.edu>
  11  * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org>
  12  * All rights reserved.
  13  *
  14  * Author: Jack Lange <jarusl@cs.northwestern.edu>
  15  *
  16  * This is free software.  You are permitted to use,
  17  * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
  18  */
  19
  20
  21 #include <palacios/vmm.h>
  22 #include <palacios/vmm_msr.h>
  23 #include <palacios/vmm_mem.h>
  24 #include <palacios/vmm_hypercall.h>
  25 #include <palacios/vm_guest.h>
  26 #include <palacios/vmm_sprintf.h>
  27
  28
  29 #define SYMSPY_GLOBAL_MSR 0x534
  30 #define SYMSPY_LOCAL_MSR 0x535
  31
  32 #define SYM_CPUID_NUM 0x90000000
  33
  34 // A succesfull symcall returns via the RET_HCALL, with the return values in registers
  35 // A symcall error returns via the ERR_HCALL with the error code in rbx
  36
  37
  38 /* Notes: We use a combination of SYSCALL and SYSENTER Semantics
  39  * SYSCALL just sets an EIP, CS/SS seg, and GS seg via swapgs
  40  * the RSP is loaded via the structure pointed to by GS
  41  * This is safe because it assumes that system calls are guaranteed to be made with an empty kernel stack.
  42  * We cannot make that assumption with a symcall, so we have to have our own stack area somewhere.
  43  * SYSTENTER does not really use the GS base MSRs, but we do to map to 64 bit kernels
  44  */
  45
  46 #define SYMCALL_RIP_MSR 0x536
  47 #define SYMCALL_RSP_MSR 0x537
  48 #define SYMCALL_CS_MSR  0x538
  49 #define SYMCALL_GS_MSR  0x539
  50 #define SYMCALL_FS_MSR  0x540
  51
  52 static int symspy_msr_read(struct guest_info * core, uint_t msr,
  53                     struct v3_msr * dst, void * priv_data) {
  54     struct v3_sym_global_state * global_state = &(core->vm_info->sym_global_state);
  55     struct v3_sym_local_state * local_state = &(core->sym_local_state);
  56
  57     switch (msr) {
  58         case SYMSPY_GLOBAL_MSR:
  59             dst->value = global_state->global_guest_pa;
  60             break;
  61         case SYMSPY_LOCAL_MSR:
  62             dst->value = local_state->local_guest_pa;
  63             break;
  64         default:
  65             return -1;
  66     }
  67
  68     return 0;
  69 }
  70
  71 static int symcall_msr_read(struct guest_info * core, uint_t msr,
  72                             struct v3_msr * dst, void * priv_data) {
  73     struct v3_symcall_state * state = &(core->sym_local_state.symcall_state);
  74
  75     switch (msr) {
  76         case SYMCALL_RIP_MSR:
  77             dst->value = state->sym_call_rip;
  78             break;
  79         case SYMCALL_RSP_MSR:
  80             dst->value = state->sym_call_rsp;
  81             break;
  82         case SYMCALL_CS_MSR:
  83             dst->value = state->sym_call_cs;
  84             break;
  85         case SYMCALL_GS_MSR:
  86             dst->value = state->sym_call_gs;
  87             break;
  88         case SYMCALL_FS_MSR:
  89             dst->value = state->sym_call_fs;
  90             break;
  91         default:
  92             return -1;
  93     }
  94
  95     return 0;
  96 }
  97
  98 static int symspy_msr_write(struct guest_info * core, uint_t msr, struct v3_msr src, void * priv_data) {
  99
 100     if (msr == SYMSPY_GLOBAL_MSR) {
 101         struct v3_sym_global_state * global_state = &(core->vm_info->sym_global_state);
 102
 103         PrintDebug("Symbiotic Glbal MSR write for page %p\n", (void *)(addr_t)src.value);
 104
 105         if (global_state->active == 1) {
 106             // unmap page
 107             struct v3_shadow_region * old_reg = v3_get_shadow_region(core->vm_info, core->cpu_id,
 108                                                                      (addr_t)global_state->global_guest_pa);
 109
 110             if (old_reg == NULL) {
 111                 PrintError("Could not find previously active symbiotic page (%p)\n",
 112                            (void *)(addr_t)global_state->global_guest_pa);
 113                 return -1;
 114             }
 115
 116             v3_delete_shadow_region(core->vm_info, old_reg);
 117         }
 118
 119         global_state->global_guest_pa = src.value;
 120         global_state->global_guest_pa &= ~0xfffLL;
 121
 122         global_state->active = 1;
 123
 124         // map page
 125         v3_add_shadow_mem(core->vm_info, V3_MEM_CORE_ANY, (addr_t)global_state->global_guest_pa,
 126                           (addr_t)(global_state->global_guest_pa + PAGE_SIZE_4KB - 1),
 127                           global_state->global_page_pa);
 128     } else if (msr == SYMSPY_LOCAL_MSR) {
 129         struct v3_sym_local_state * local_state = &(core->sym_local_state);
 130
 131         PrintDebug("Symbiotic Local MSR write for page %p\n", (void *)(addr_t)src.value);
 132
 133         if (local_state->active == 1) {
 134             // unmap page
 135             struct v3_shadow_region * old_reg = v3_get_shadow_region(core->vm_info, core->cpu_id,
 136                                                                      (addr_t)local_state->local_guest_pa);
 137
 138             if (old_reg == NULL) {
 139                 PrintError("Could not find previously active symbiotic page (%p)\n",
 140                            (void *)(addr_t)local_state->local_guest_pa);
 141                 return -1;
 142             }
 143
 144             v3_delete_shadow_region(core->vm_info, old_reg);
 145         }
 146
 147         local_state->local_guest_pa = src.value;
 148         local_state->local_guest_pa &= ~0xfffLL;
 149
 150         local_state->active = 1;
 151
 152         // map page
 153         v3_add_shadow_mem(core->vm_info, core->cpu_id, (addr_t)local_state->local_guest_pa,
 154                           (addr_t)(local_state->local_guest_pa + PAGE_SIZE_4KB - 1),
 155                           local_state->local_page_pa);
 156     } else {
 157         PrintError("Invalid Symbiotic MSR write (0x%x)\n", msr);
 158         return -1;
 159     }
 160
 161     return 0;
 162 }
 163
 164
 165 static int symcall_msr_write(struct guest_info * core, uint_t msr, struct v3_msr src, void * priv_data) {
 166     struct v3_symcall_state * state = &(core->sym_local_state.symcall_state);
 167
 168     switch (msr) {
 169         case SYMCALL_RIP_MSR:
 170             state->sym_call_rip = src.value;
 171             break;
 172         case SYMCALL_RSP_MSR:
 173             state->sym_call_rsp = src.value;
 174             break;
 175         case SYMCALL_CS_MSR:
 176             state->sym_call_cs = src.value;
 177             break;
 178         case SYMCALL_GS_MSR:
 179             state->sym_call_gs = src.value;
 180             break;
 181         case SYMCALL_FS_MSR:
 182             state->sym_call_fs = src.value;
 183             break;
 184         default:
 185             PrintError("Invalid Symbiotic MSR write (0x%x)\n", msr);
 186             return -1;
 187     }
 188     return 0;
 189 }
 190
 191 static int cpuid_fn(struct guest_info * core, uint32_t cpuid,
 192                     uint32_t * eax, uint32_t * ebx,
 193                     uint32_t * ecx, uint32_t * edx,
 194                     void * private_data) {
 195     extern v3_cpu_arch_t v3_cpu_types[];
 196
 197     *eax = *(uint32_t *)"V3V";
 198
 199     if ((v3_cpu_types[core->cpu_id] == V3_SVM_CPU) ||
 200         (v3_cpu_types[core->cpu_id] == V3_SVM_REV3_CPU)) {
 201         *ebx = *(uint32_t *)"SVM";
 202     } else if ((v3_cpu_types[core->cpu_id] == V3_VMX_CPU) ||
 203                (v3_cpu_types[core->cpu_id] == V3_VMX_EPT_CPU)) {
 204         *ebx = *(uint32_t *)"VMX";
 205     }
 206
 207
 208     return 0;
 209 }
 210
 211
 212 static int sym_call_ret(struct guest_info * info, uint_t hcall_id, void * private_data);
 213 static int sym_call_err(struct guest_info * info, uint_t hcall_id, void * private_data);
 214
 215
 216
 217 int v3_init_sym_iface(struct v3_vm_info * vm) {
 218     struct v3_sym_global_state * global_state = &(vm->sym_global_state);
 219     memset(global_state, 0, sizeof(struct v3_sym_global_state));
 220
 221     global_state->global_page_pa = (addr_t)V3_AllocPages(1);
 222     global_state->sym_page = (struct v3_sym_global_page *)V3_VAddr((void *)global_state->global_page_pa);
 223     memset(global_state->sym_page, 0, PAGE_SIZE_4KB);
 224
 225     memcpy(&(global_state->sym_page->magic), "V3V", 3);
 226
 227     v3_hook_msr(vm, SYMSPY_LOCAL_MSR, symspy_msr_read, symspy_msr_write, NULL);
 228     v3_hook_msr(vm, SYMSPY_GLOBAL_MSR, symspy_msr_read, symspy_msr_write, NULL);
 229
 230     v3_hook_cpuid(vm, SYM_CPUID_NUM, cpuid_fn, NULL);
 231
 232     v3_hook_msr(vm, SYMCALL_RIP_MSR, symcall_msr_read, symcall_msr_write, NULL);
 233     v3_hook_msr(vm, SYMCALL_RSP_MSR, symcall_msr_read, symcall_msr_write, NULL);
 234     v3_hook_msr(vm, SYMCALL_CS_MSR, symcall_msr_read, symcall_msr_write, NULL);
 235     v3_hook_msr(vm, SYMCALL_GS_MSR, symcall_msr_read, symcall_msr_write, NULL);
 236     v3_hook_msr(vm, SYMCALL_FS_MSR, symcall_msr_read, symcall_msr_write, NULL);
 237
 238     v3_register_hypercall(vm, SYMCALL_RET_HCALL, sym_call_ret, NULL);
 239     v3_register_hypercall(vm, SYMCALL_ERR_HCALL, sym_call_err, NULL);
 240
 241     return 0;
 242 }
 243
 244
 245 int v3_init_sym_core(struct guest_info * core) {
 246     struct v3_sym_local_state * local_state = &(core->sym_local_state);
 247     memset(local_state, 0, sizeof(struct v3_sym_local_state));
 248
 249     local_state->local_page_pa = (addr_t)V3_AllocPages(1);
 250     local_state->local_page = (struct v3_sym_local_page *)V3_VAddr((void *)local_state->local_page_pa);
 251     memset(local_state->local_page, 0, PAGE_SIZE_4KB);
 252
 253     snprintf((uint8_t *)&(local_state->local_page->magic), 8, "V3V.%d", core->cpu_id);
 254
 255     return 0;
 256 }
 257
 258
 259 int v3_sym_map_pci_passthrough(struct v3_vm_info * vm, uint_t bus, uint_t dev, uint_t fn) {
 260     struct v3_sym_global_state * global_state = &(vm->sym_global_state);
 261     uint_t dev_index = (bus << 8) + (dev << 3) + fn;
 262     uint_t major = dev_index / 8;
 263     uint_t minor = dev_index % 8;
 264
 265     if (bus > 3) {
 266         PrintError("Invalid PCI bus %d\n", bus);
 267         return -1;
 268     }
 269
 270     PrintDebug("Setting passthrough pci map for index=%d\n", dev_index);
 271
 272     global_state->sym_page->pci_pt_map[major] |= 0x1 << minor;
 273
 274     PrintDebug("pt_map entry=%x\n",   global_state->sym_page->pci_pt_map[major]);
 275
 276     PrintDebug("pt map vmm addr=%p\n", global_state->sym_page->pci_pt_map);
 277
 278     return 0;
 279 }
 280
 281 int v3_sym_unmap_pci_passthrough(struct v3_vm_info * vm, uint_t bus, uint_t dev, uint_t fn) {
 282     struct v3_sym_global_state * global_state = &(vm->sym_global_state);
 283     uint_t dev_index = (bus << 8) + (dev << 3) + fn;
 284     uint_t major = dev_index / 8;
 285     uint_t minor = dev_index % 8;
 286
 287     if (bus > 3) {
 288         PrintError("Invalid PCI bus %d\n", bus);
 289         return -1;
 290     }
 291
 292     global_state->sym_page->pci_pt_map[major] &= ~(0x1 << minor);
 293
 294     return 0;
 295 }
 296
 297
 298 static int sym_call_err(struct guest_info * core, uint_t hcall_id, void * private_data) {
 299     struct v3_symcall_state * state = (struct v3_symcall_state *)&(core->sym_local_state.symcall_state);
 300
 301     PrintError("sym call error\n");
 302
 303     state->sym_call_errno = (int)core->vm_regs.rbx;
 304     v3_print_guest_state(core);
 305     v3_print_mem_map(core->vm_info);
 306
 307     // clear sym flags
 308     state->sym_call_error = 1;
 309     state->sym_call_returned = 1;
 310
 311     return -1;
 312 }
 313
 314 static int sym_call_ret(struct guest_info * core, uint_t hcall_id, void * private_data) {
 315     struct v3_symcall_state * state = (struct v3_symcall_state *)&(core->sym_local_state.symcall_state);
 316
 317     //    PrintError("Return from sym call (ID=%x)\n", hcall_id);
 318     //   v3_print_guest_state(info);
 319
 320     state->sym_call_returned = 1;
 321
 322     return 0;
 323 }
 324
 325 static int execute_symcall(struct guest_info * core) {
 326     struct v3_symcall_state * state = (struct v3_symcall_state *)&(core->sym_local_state.symcall_state);
 327
 328     while (state->sym_call_returned == 0) {
 329         if (v3_vm_enter(core) == -1) {
 330             PrintError("Error in Sym call\n");
 331             return -1;
 332         }
 333     }
 334
 335     return 0;
 336 }
 337
 338
 339 int v3_sym_call(struct guest_info * core,
 340                 uint64_t call_num, sym_arg_t * arg0,
 341                 sym_arg_t * arg1, sym_arg_t * arg2,
 342                 sym_arg_t * arg3, sym_arg_t * arg4) {
 343     struct v3_sym_local_state * sym_state = (struct v3_sym_local_state *)&(core->sym_local_state);
 344     struct v3_symcall_state * state = (struct v3_symcall_state *)&(sym_state->symcall_state);
 345     struct v3_sym_cpu_context * old_ctx = (struct v3_sym_cpu_context *)&(state->old_ctx);
 346     struct v3_segment sym_cs;
 347     struct v3_segment sym_ss;
 348     uint64_t trash_args[5] = { [0 ... 4] = 0 };
 349
 350     //   PrintDebug("Making Sym call\n");
 351     //    v3_print_guest_state(info);
 352
 353     if ((sym_state->local_page->sym_call_enabled == 0) ||
 354         (state->sym_call_active == 1)) {
 355         return -1;
 356     }
 357
 358     if (!arg0) arg0 = &trash_args[0];
 359     if (!arg1) arg1 = &trash_args[1];
 360     if (!arg2) arg2 = &trash_args[2];
 361     if (!arg3) arg3 = &trash_args[3];
 362     if (!arg4) arg4 = &trash_args[4];
 363
 364     // Save the old context
 365     memcpy(&(old_ctx->vm_regs), &(core->vm_regs), sizeof(struct v3_gprs));
 366     memcpy(&(old_ctx->cs), &(core->segments.cs), sizeof(struct v3_segment));
 367     memcpy(&(old_ctx->ss), &(core->segments.ss), sizeof(struct v3_segment));
 368     old_ctx->gs_base = core->segments.gs.base;
 369     old_ctx->fs_base = core->segments.fs.base;
 370     old_ctx->rip = core->rip;
 371     old_ctx->cpl = core->cpl;
 372     old_ctx->flags = core->ctrl_regs.rflags;
 373
 374     // Setup the sym call context
 375     core->rip = state->sym_call_rip;
 376     core->vm_regs.rsp = state->sym_call_rsp; // old contest rsp is saved in vm_regs
 377
 378     v3_translate_segment(core, state->sym_call_cs, &sym_cs);
 379     memcpy(&(core->segments.cs), &sym_cs, sizeof(struct v3_segment));
 380
 381     v3_translate_segment(core, state->sym_call_cs + 8, &sym_ss);
 382     memcpy(&(core->segments.ss), &sym_ss, sizeof(struct v3_segment));
 383
 384     core->segments.gs.base = state->sym_call_gs;
 385     core->segments.fs.base = state->sym_call_fs;
 386     core->cpl = 0;
 387
 388     core->vm_regs.rax = call_num;
 389     core->vm_regs.rbx = *arg0;
 390     core->vm_regs.rcx = *arg1;
 391     core->vm_regs.rdx = *arg2;
 392     core->vm_regs.rsi = *arg3;
 393     core->vm_regs.rdi = *arg4;
 394
 395     // Mark sym call as active
 396     state->sym_call_active = 1;
 397     state->sym_call_returned = 0;
 398
 399     //    PrintDebug("Sym state\n");
 400     //  v3_print_guest_state(core);
 401
 402     // Do the sym call entry
 403     if (execute_symcall(core) == -1) {
 404         PrintError("SYMCALL error\n");
 405         return -1;
 406     }
 407
 408     // clear sym flags
 409     state->sym_call_active = 0;
 410
 411     *arg0 = core->vm_regs.rbx;
 412     *arg1 = core->vm_regs.rcx;
 413     *arg2 = core->vm_regs.rdx;
 414     *arg3 = core->vm_regs.rsi;
 415     *arg4 = core->vm_regs.rdi;
 416
 417     // restore guest state
 418     memcpy(&(core->vm_regs), &(old_ctx->vm_regs), sizeof(struct v3_gprs));
 419     memcpy(&(core->segments.cs), &(old_ctx->cs), sizeof(struct v3_segment));
 420     memcpy(&(core->segments.ss), &(old_ctx->ss), sizeof(struct v3_segment));
 421     core->segments.gs.base = old_ctx->gs_base;
 422     core->segments.fs.base = old_ctx->fs_base;
 423     core->rip = old_ctx->rip;
 424     core->cpl = old_ctx->cpl;
 425     core->ctrl_regs.rflags = old_ctx->flags;
 426
 427
 428
 429     //    PrintError("restoring guest state\n");
 430     //    v3_print_guest_state(core);
 431
 432     return 0;
 433 }
 434
 435