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 #define SYM_CALL_RET_HCALL 0x535
  37 #define SYM_CALL_ERR_HCALL 0x536
  38
  39
  40 /* Notes: We use a combination of SYSCALL and SYSENTER Semantics
  41  * SYSCALL just sets an EIP, CS/SS seg, and GS seg via swapgs
  42  * the RSP is loaded via the structure pointed to by GS
  43  * This is safe because it assumes that system calls are guaranteed to be made with an empty kernel stack.
  44  * We cannot make that assumption with a symcall, so we have to have our own stack area somewhere.
  45  * SYSTENTER does not really use the GS base MSRs, but we do to map to 64 bit kernels
  46  */
  47
  48 #define SYMCALL_RIP_MSR 0x536
  49 #define SYMCALL_RSP_MSR 0x537
  50 #define SYMCALL_CS_MSR  0x538
  51 #define SYMCALL_GS_MSR  0x539
  52 #define SYMCALL_FS_MSR  0x540
  53
  54 static int symspy_msr_read(struct guest_info * core, uint_t msr,
  55                     struct v3_msr * dst, void * priv_data) {
  56     struct v3_sym_global_state * global_state = &(core->vm_info->sym_global_state);
  57     struct v3_sym_local_state * local_state = &(core->sym_local_state);
  58
  59     switch (msr) {
  60         case SYMSPY_GLOBAL_MSR:
  61             dst->value = global_state->global_guest_pa;
  62             break;
  63         case SYMSPY_LOCAL_MSR:
  64             dst->value = local_state->local_guest_pa;
  65             break;
  66         default:
  67             return -1;
  68     }
  69
  70     return 0;
  71 }
  72
  73 static int symcall_msr_read(struct guest_info * core, uint_t msr,
  74                             struct v3_msr * dst, void * priv_data) {
  75     struct v3_symcall_state * state = &(core->sym_local_state.symcall_state);
  76
  77     switch (msr) {
  78         case SYMCALL_RIP_MSR:
  79             dst->value = state->sym_call_rip;
  80             break;
  81         case SYMCALL_RSP_MSR:
  82             dst->value = state->sym_call_rsp;
  83             break;
  84         case SYMCALL_CS_MSR:
  85             dst->value = state->sym_call_cs;
  86             break;
  87         case SYMCALL_GS_MSR:
  88             dst->value = state->sym_call_gs;
  89             break;
  90         case SYMCALL_FS_MSR:
  91             dst->value = state->sym_call_fs;
  92             break;
  93         default:
  94             return -1;
  95     }
  96
  97     return 0;
  98 }
  99
 100 static int symspy_msr_write(struct guest_info * core, uint_t msr, struct v3_msr src, void * priv_data) {
 101
 102     if (msr == SYMSPY_GLOBAL_MSR) {
 103         struct v3_sym_global_state * global_state = &(core->vm_info->sym_global_state);
 104
 105         PrintDebug("Symbiotic Glbal MSR write for page %p\n", (void *)(addr_t)src.value);
 106
 107         if (global_state->active == 1) {
 108             // unmap page
 109             struct v3_shadow_region * old_reg = v3_get_shadow_region(core->vm_info, core->cpu_id,
 110                                                                      (addr_t)global_state->global_guest_pa);
 111
 112             if (old_reg == NULL) {
 113                 PrintError("Could not find previously active symbiotic page (%p)\n",
 114                            (void *)(addr_t)global_state->global_guest_pa);
 115                 return -1;
 116             }
 117
 118             v3_delete_shadow_region(core->vm_info, old_reg);
 119         }
 120
 121         global_state->global_guest_pa = src.value;
 122         global_state->global_guest_pa &= ~0xfffLL;
 123
 124         global_state->active = 1;
 125
 126         // map page
 127         v3_add_shadow_mem(core->vm_info, V3_MEM_CORE_ANY, (addr_t)global_state->global_guest_pa,
 128                           (addr_t)(global_state->global_guest_pa + PAGE_SIZE_4KB - 1),
 129                           global_state->global_page_pa);
 130     } else if (msr == SYMSPY_LOCAL_MSR) {
 131         struct v3_sym_local_state * local_state = &(core->sym_local_state);
 132
 133         PrintDebug("Symbiotic Local MSR write for page %p\n", (void *)(addr_t)src.value);
 134
 135         if (local_state->active == 1) {
 136             // unmap page
 137             struct v3_shadow_region * old_reg = v3_get_shadow_region(core->vm_info, core->cpu_id,
 138                                                                      (addr_t)local_state->local_guest_pa);
 139
 140             if (old_reg == NULL) {
 141                 PrintError("Could not find previously active symbiotic page (%p)\n",
 142                            (void *)(addr_t)local_state->local_guest_pa);
 143                 return -1;
 144             }
 145
 146             v3_delete_shadow_region(core->vm_info, old_reg);
 147         }
 148
 149         local_state->local_guest_pa = src.value;
 150         local_state->local_guest_pa &= ~0xfffLL;
 151
 152         local_state->active = 1;
 153
 154         // map page
 155         v3_add_shadow_mem(core->vm_info, core->cpu_id, (addr_t)local_state->local_guest_pa,
 156                           (addr_t)(local_state->local_guest_pa + PAGE_SIZE_4KB - 1),
 157                           local_state->local_page_pa);
 158     } else {
 159         PrintError("Invalid Symbiotic MSR write (0x%x)\n", msr);
 160         return -1;
 161     }
 162
 163     return 0;
 164 }
 165
 166
 167 static int symcall_msr_write(struct guest_info * core, uint_t msr, struct v3_msr src, void * priv_data) {
 168     struct v3_symcall_state * state = &(core->sym_local_state.symcall_state);
 169
 170     switch (msr) {
 171         case SYMCALL_RIP_MSR:
 172             state->sym_call_rip = src.value;
 173             break;
 174         case SYMCALL_RSP_MSR:
 175             state->sym_call_rsp = src.value;
 176             break;
 177         case SYMCALL_CS_MSR:
 178             state->sym_call_cs = src.value;
 179             break;
 180         case SYMCALL_GS_MSR:
 181             state->sym_call_gs = src.value;
 182             break;
 183         case SYMCALL_FS_MSR:
 184             state->sym_call_fs = src.value;
 185             break;
 186         default:
 187             PrintError("Invalid Symbiotic MSR write (0x%x)\n", msr);
 188             return -1;
 189     }
 190     return 0;
 191 }
 192
 193 static int cpuid_fn(struct guest_info * core, uint32_t cpuid,
 194                     uint32_t * eax, uint32_t * ebx,
 195                     uint32_t * ecx, uint32_t * edx,
 196                     void * private_data) {
 197     extern v3_cpu_arch_t v3_cpu_types[];
 198
 199     *eax = *(uint32_t *)"V3V";
 200
 201     if ((v3_cpu_types[core->cpu_id] == V3_SVM_CPU) ||
 202         (v3_cpu_types[core->cpu_id] == V3_SVM_REV3_CPU)) {
 203         *ebx = *(uint32_t *)"SVM";
 204     } else if ((v3_cpu_types[core->cpu_id] == V3_VMX_CPU) ||
 205                (v3_cpu_types[core->cpu_id] == V3_VMX_EPT_CPU)) {
 206         *ebx = *(uint32_t *)"VMX";
 207     }
 208
 209
 210     return 0;
 211 }
 212
 213
 214 static int sym_call_ret(struct guest_info * info, uint_t hcall_id, void * private_data);
 215 static int sym_call_err(struct guest_info * info, uint_t hcall_id, void * private_data);
 216
 217
 218
 219 int v3_init_sym_iface(struct v3_vm_info * vm) {
 220     struct v3_sym_global_state * global_state = &(vm->sym_global_state);
 221     memset(global_state, 0, sizeof(struct v3_sym_global_state));
 222
 223     global_state->global_page_pa = (addr_t)V3_AllocPages(1);
 224     global_state->sym_page = (struct v3_sym_global_page *)V3_VAddr((void *)global_state->global_page_pa);
 225     memset(global_state->sym_page, 0, PAGE_SIZE_4KB);
 226
 227     memcpy(&(global_state->sym_page->magic), "V3V", 3);
 228
 229     v3_hook_msr(vm, SYMSPY_LOCAL_MSR, symspy_msr_read, symspy_msr_write, NULL);
 230     v3_hook_msr(vm, SYMSPY_GLOBAL_MSR, symspy_msr_read, symspy_msr_write, NULL);
 231
 232     v3_hook_cpuid(vm, SYM_CPUID_NUM, cpuid_fn, NULL);
 233
 234     v3_hook_msr(vm, SYMCALL_RIP_MSR, symcall_msr_read, symcall_msr_write, NULL);
 235     v3_hook_msr(vm, SYMCALL_RSP_MSR, symcall_msr_read, symcall_msr_write, NULL);
 236     v3_hook_msr(vm, SYMCALL_CS_MSR, symcall_msr_read, symcall_msr_write, NULL);
 237     v3_hook_msr(vm, SYMCALL_GS_MSR, symcall_msr_read, symcall_msr_write, NULL);
 238     v3_hook_msr(vm, SYMCALL_FS_MSR, symcall_msr_read, symcall_msr_write, NULL);
 239
 240     v3_register_hypercall(vm, SYM_CALL_RET_HCALL, sym_call_ret, NULL);
 241     v3_register_hypercall(vm, SYM_CALL_ERR_HCALL, sym_call_err, NULL);
 242
 243     return 0;
 244 }
 245
 246
 247 int v3_init_sym_core(struct guest_info * core) {
 248     struct v3_sym_local_state * local_state = &(core->sym_local_state);
 249     memset(local_state, 0, sizeof(struct v3_sym_local_state));
 250
 251     local_state->local_page_pa = (addr_t)V3_AllocPages(1);
 252     local_state->local_page = (struct v3_sym_local_page *)V3_VAddr((void *)local_state->local_page_pa);
 253     memset(local_state->local_page, 0, PAGE_SIZE_4KB);
 254
 255     snprintf((uint8_t *)&(local_state->local_page->magic), 8, "V3V.%d", core->cpu_id);
 256
 257     return 0;
 258 }
 259
 260
 261 int v3_sym_map_pci_passthrough(struct v3_vm_info * vm, uint_t bus, uint_t dev, uint_t fn) {
 262     struct v3_sym_global_state * global_state = &(vm->sym_global_state);
 263     uint_t dev_index = (bus << 8) + (dev << 3) + fn;
 264     uint_t major = dev_index / 8;
 265     uint_t minor = dev_index % 8;
 266
 267     if (bus > 3) {
 268         PrintError("Invalid PCI bus %d\n", bus);
 269         return -1;
 270     }
 271
 272     PrintDebug("Setting passthrough pci map for index=%d\n", dev_index);
 273
 274     global_state->sym_page->pci_pt_map[major] |= 0x1 << minor;
 275
 276     PrintDebug("pt_map entry=%x\n",   global_state->sym_page->pci_pt_map[major]);
 277
 278     PrintDebug("pt map vmm addr=%p\n", global_state->sym_page->pci_pt_map);
 279
 280     return 0;
 281 }
 282
 283 int v3_sym_unmap_pci_passthrough(struct v3_vm_info * vm, uint_t bus, uint_t dev, uint_t fn) {
 284     struct v3_sym_global_state * global_state = &(vm->sym_global_state);
 285     uint_t dev_index = (bus << 8) + (dev << 3) + fn;
 286     uint_t major = dev_index / 8;
 287     uint_t minor = dev_index % 8;
 288
 289     if (bus > 3) {
 290         PrintError("Invalid PCI bus %d\n", bus);
 291         return -1;
 292     }
 293
 294     global_state->sym_page->pci_pt_map[major] &= ~(0x1 << minor);
 295
 296     return 0;
 297 }
 298
 299
 300 static int sym_call_err(struct guest_info * core, uint_t hcall_id, void * private_data) {
 301     struct v3_symcall_state * state = (struct v3_symcall_state *)&(core->sym_local_state.symcall_state);
 302
 303     PrintError("sym call error\n");
 304
 305     state->sym_call_errno = (int)core->vm_regs.rbx;
 306     v3_print_guest_state(core);
 307     v3_print_mem_map(core->vm_info);
 308
 309     // clear sym flags
 310     state->sym_call_error = 1;
 311     state->sym_call_returned = 1;
 312
 313     return -1;
 314 }
 315
 316 static int sym_call_ret(struct guest_info * core, uint_t hcall_id, void * private_data) {
 317     struct v3_symcall_state * state = (struct v3_symcall_state *)&(core->sym_local_state.symcall_state);
 318
 319     //    PrintError("Return from sym call (ID=%x)\n", hcall_id);
 320     //   v3_print_guest_state(info);
 321
 322     state->sym_call_returned = 1;
 323
 324     return 0;
 325 }
 326
 327 static int execute_symcall(struct guest_info * core) {
 328     struct v3_symcall_state * state = (struct v3_symcall_state *)&(core->sym_local_state.symcall_state);
 329
 330     while (state->sym_call_returned == 0) {
 331         if (v3_vm_enter(core) == -1) {
 332             PrintError("Error in Sym call\n");
 333             return -1;
 334         }
 335     }
 336
 337     return 0;
 338 }
 339
 340
 341 int v3_sym_call(struct guest_info * core,
 342                 uint64_t call_num, sym_arg_t * arg0,
 343                 sym_arg_t * arg1, sym_arg_t * arg2,
 344                 sym_arg_t * arg3, sym_arg_t * arg4) {
 345     struct v3_sym_local_state * sym_state = (struct v3_sym_local_state *)&(core->sym_local_state);
 346     struct v3_symcall_state * state = (struct v3_symcall_state *)&(sym_state->symcall_state);
 347     struct v3_sym_cpu_context * old_ctx = (struct v3_sym_cpu_context *)&(state->old_ctx);
 348     struct v3_segment sym_cs;
 349     struct v3_segment sym_ss;
 350     uint64_t trash_args[5] = { [0 ... 4] = 0 };
 351
 352     //   PrintDebug("Making Sym call\n");
 353     //    v3_print_guest_state(info);
 354
 355     if ((sym_state->local_page->sym_call_enabled == 0) ||
 356         (state->sym_call_active == 1)) {
 357         return -1;
 358     }
 359
 360     if (!arg0) arg0 = &trash_args[0];
 361     if (!arg1) arg1 = &trash_args[1];
 362     if (!arg2) arg2 = &trash_args[2];
 363     if (!arg3) arg3 = &trash_args[3];
 364     if (!arg4) arg4 = &trash_args[4];
 365
 366     // Save the old context
 367     memcpy(&(old_ctx->vm_regs), &(core->vm_regs), sizeof(struct v3_gprs));
 368     memcpy(&(old_ctx->cs), &(core->segments.cs), sizeof(struct v3_segment));
 369     memcpy(&(old_ctx->ss), &(core->segments.ss), sizeof(struct v3_segment));
 370     old_ctx->gs_base = core->segments.gs.base;
 371     old_ctx->fs_base = core->segments.fs.base;
 372     old_ctx->rip = core->rip;
 373     old_ctx->cpl = core->cpl;
 374     old_ctx->flags = core->ctrl_regs.rflags;
 375
 376     // Setup the sym call context
 377     core->rip = state->sym_call_rip;
 378     core->vm_regs.rsp = state->sym_call_rsp; // old contest rsp is saved in vm_regs
 379
 380     v3_translate_segment(core, state->sym_call_cs, &sym_cs);
 381     memcpy(&(core->segments.cs), &sym_cs, sizeof(struct v3_segment));
 382
 383     v3_translate_segment(core, state->sym_call_cs + 8, &sym_ss);
 384     memcpy(&(core->segments.ss), &sym_ss, sizeof(struct v3_segment));
 385
 386     core->segments.gs.base = state->sym_call_gs;
 387     core->segments.fs.base = state->sym_call_fs;
 388     core->cpl = 0;
 389
 390     core->vm_regs.rax = call_num;
 391     core->vm_regs.rbx = *arg0;
 392     core->vm_regs.rcx = *arg1;
 393     core->vm_regs.rdx = *arg2;
 394     core->vm_regs.rsi = *arg3;
 395     core->vm_regs.rdi = *arg4;
 396
 397     // Mark sym call as active
 398     state->sym_call_active = 1;
 399     state->sym_call_returned = 0;
 400
 401     //    PrintDebug("Sym state\n");
 402     //  v3_print_guest_state(core);
 403
 404     // Do the sym call entry
 405     if (execute_symcall(core) == -1) {
 406         PrintError("SYMCALL error\n");
 407         return -1;
 408     }
 409
 410     // clear sym flags
 411     state->sym_call_active = 0;
 412
 413     *arg0 = core->vm_regs.rbx;
 414     *arg1 = core->vm_regs.rcx;
 415     *arg2 = core->vm_regs.rdx;
 416     *arg3 = core->vm_regs.rsi;
 417     *arg4 = core->vm_regs.rdi;
 418
 419     // restore guest state
 420     memcpy(&(core->vm_regs), &(old_ctx->vm_regs), sizeof(struct v3_gprs));
 421     memcpy(&(core->segments.cs), &(old_ctx->cs), sizeof(struct v3_segment));
 422     memcpy(&(core->segments.ss), &(old_ctx->ss), sizeof(struct v3_segment));
 423     core->segments.gs.base = old_ctx->gs_base;
 424     core->segments.fs.base = old_ctx->fs_base;
 425     core->rip = old_ctx->rip;
 426     core->cpl = old_ctx->cpl;
 427     core->ctrl_regs.rflags = old_ctx->flags;
 428
 429
 430
 431     //    PrintError("restoring guest state\n");
 432     //    v3_print_guest_state(core);
 433
 434     return 0;
 435 }
 436
 437