vmcb.c revision 249967
1/*- 2 * Copyright (c) 2013 Anish Gupta (akgupt3@gmail.com) 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: projects/bhyve_svm/sys/amd64/vmm/amd/vmcb.c 249967 2013-04-27 04:49:51Z neel $"); 29 30#include <sys/param.h> 31#include <sys/systm.h> 32#include <sys/cpuset.h> 33 34#include <machine/segments.h> 35#include <machine/specialreg.h> 36#include <machine/vmm.h> 37 38#include "vmcb.h" 39#include "svm.h" 40 41/* 42 * The VMCB aka Virtual Machine Control Block is a 4KB aligned page 43 * in memory that describes the virtual machine. 44 * 45 * The VMCB contains: 46 * - instructions or events in the guest to intercept 47 * - control bits that modify execution environment of the guest 48 * - guest processor state (e.g. general purpose registers) 49 */ 50 51/* 52 * Initialize SVM h/w context i.e. the VMCB control and saved state areas. 53 */ 54int 55svm_init_vmcb(struct vmcb *vmcb, uint64_t iopm_base_pa, 56 uint64_t msrpm_base_pa, uint64_t np_pml4) 57{ 58 struct vmcb_ctrl *ctrl; 59 struct vmcb_state *state; 60 61 ctrl = &vmcb->ctrl; 62 state = &vmcb->state; 63 64 ctrl->iopm_base_pa = iopm_base_pa; 65 ctrl->msrpm_base_pa = msrpm_base_pa; 66 67 /* Enable nested paging */ 68 ctrl->np_enable = 1; 69 ctrl->n_cr3 = np_pml4; 70 71 /* EFER_SVM must always be set when the guest is executing */ 72 state->efer = EFER_SVM; 73 74 return (0); 75} 76 77/* 78 * Set non-persistent fields of VMCB that are cleared by VMEXIT and must 79 * be set before restarting the guest (e.g. ASID, intercepts etc). 80 * 81 * APM2, Section 15.6, VMEXIT 82 */ 83int 84svm_set_vmcb(struct vmcb *vmcb, uint8_t asid) 85{ 86 struct vmcb_ctrl *ctrl; 87 struct vmcb_state *state; 88 uint16_t cr_shadow; 89 90 ctrl = &vmcb->ctrl; 91 state = &vmcb->state; 92 93 /* 94 * Intercept accesses to the control registers that are not shadowed 95 * in the VMCB - i.e. all except cr0, cr2, cr3, cr4 and cr8. 96 */ 97 cr_shadow = BIT(0) | BIT(2) | BIT(3) | BIT(4) | BIT(8); 98 ctrl->cr_write = ctrl->cr_read = ~cr_shadow; 99 100 /* Intercept Machine Check exceptions. */ 101 ctrl->exception = BIT(IDT_MC); 102 103 /* Intercept various events (for e.g. I/O, MSR and CPUID accesses) */ 104 ctrl->ctrl1 = VMCB_INTCPT_IO | 105 VMCB_INTCPT_MSR | 106 VMCB_INTCPT_HLT | 107 VMCB_INTCPT_CPUID | 108 VMCB_INTCPT_INTR | 109 VMCB_INTCPT_VINTR | 110 VMCB_INTCPT_INIT | 111 VMCB_INTCPT_NMI | 112 VMCB_INTCPT_SMI | 113 VMCB_INTCPT_FERR_FREEZE | 114 VMCB_INTCPT_SHUTDOWN; 115 116 /* VMRUN intercept is required, see APM2 */ 117 ctrl->ctrl2 = VMCB_INTCPT_VMRUN; 118 119 /* ASID is cleared after every #VMEXIT. */ 120 ctrl->asid = asid; 121 122 /* 123 * Section 15.21.1, Interrupt Masking in EFLAGS 124 * Section 15.21.2, Virtualizing APIC.TPR 125 * 126 * This must be set for %rflag and %cr8 isolation of guest and host. 127 */ 128 ctrl->v_intr_masking = 1; 129 130 /* Enable Last Branch Record aka LBR for debugging */ 131 ctrl->lbr_virt_en = 1; 132 state->dbgctl = BIT(0); 133 134 return (0); 135} 136 137/* 138 * Read from segment selector, control and general purpose register of VMCB. 139 */ 140int 141vmcb_read(struct vmcb *vmcb, int ident, uint64_t *retval) 142{ 143 struct vmcb_state *state; 144 struct vmcb_segment *seg; 145 int err; 146 147 state = &vmcb->state; 148 err = 0; 149 150 switch (ident) { 151 case VM_REG_GUEST_CR0: 152 *retval = state->cr0; 153 break; 154 155 case VM_REG_GUEST_CR3: 156 *retval = state->cr3; 157 break; 158 159 case VM_REG_GUEST_CR4: 160 *retval = state->cr4; 161 break; 162 163 case VM_REG_GUEST_DR7: 164 *retval = state->dr7; 165 break; 166 167 case VM_REG_GUEST_EFER: 168 *retval = state->efer; 169 break; 170 171 case VM_REG_GUEST_RAX: 172 *retval = state->rax; 173 break; 174 175 case VM_REG_GUEST_RFLAGS: 176 *retval = state->rflags; 177 break; 178 179 case VM_REG_GUEST_RIP: 180 *retval = state->rip; 181 break; 182 183 case VM_REG_GUEST_RSP: 184 *retval = state->rsp; 185 break; 186 187 case VM_REG_GUEST_CS: 188 case VM_REG_GUEST_DS: 189 case VM_REG_GUEST_ES: 190 case VM_REG_GUEST_FS: 191 case VM_REG_GUEST_GS: 192 case VM_REG_GUEST_SS: 193 case VM_REG_GUEST_GDTR: 194 case VM_REG_GUEST_IDTR: 195 case VM_REG_GUEST_LDTR: 196 case VM_REG_GUEST_TR: 197 seg = vmcb_seg(vmcb, ident); 198 if (seg == NULL) { 199 ERR("Invalid seg type %d\n", ident); 200 err = EINVAL; 201 break; 202 } 203 204 *retval = seg->selector; 205 break; 206 207 default: 208 err = EINVAL; 209 break; 210 } 211 212 return (err); 213} 214 215/* 216 * Write to segment selector, control and general purpose register of VMCB. 217 */ 218int 219vmcb_write(struct vmcb *vmcb, int ident, uint64_t val) 220{ 221 struct vmcb_state *state; 222 struct vmcb_segment *seg; 223 int err; 224 225 state = &vmcb->state; 226 err = 0; 227 228 switch (ident) { 229 case VM_REG_GUEST_CR0: 230 state->cr0 = val; 231 break; 232 233 case VM_REG_GUEST_CR3: 234 state->cr3 = val; 235 break; 236 237 case VM_REG_GUEST_CR4: 238 state->cr4 = val; 239 break; 240 241 case VM_REG_GUEST_DR7: 242 state->dr7 = val; 243 break; 244 245 case VM_REG_GUEST_EFER: 246 /* EFER_SVM must always be set when the guest is executing */ 247 state->efer = val | EFER_SVM; 248 break; 249 250 case VM_REG_GUEST_RAX: 251 state->rax = val; 252 break; 253 254 case VM_REG_GUEST_RFLAGS: 255 state->rflags = val; 256 break; 257 258 case VM_REG_GUEST_RIP: 259 state->rip = val; 260 break; 261 262 case VM_REG_GUEST_RSP: 263 state->rsp = val; 264 break; 265 266 case VM_REG_GUEST_CS: 267 case VM_REG_GUEST_DS: 268 case VM_REG_GUEST_ES: 269 case VM_REG_GUEST_FS: 270 case VM_REG_GUEST_GS: 271 case VM_REG_GUEST_SS: 272 case VM_REG_GUEST_GDTR: 273 case VM_REG_GUEST_IDTR: 274 case VM_REG_GUEST_LDTR: 275 case VM_REG_GUEST_TR: 276 seg = vmcb_seg(vmcb, ident); 277 if (seg == NULL) { 278 ERR("Invalid segment type %d\n", ident); 279 err = EINVAL; 280 break; 281 } 282 283 seg->selector = val; 284 break; 285 286 default: 287 err = EINVAL; 288 } 289 290 return (err); 291} 292 293/* 294 * Return VMCB segment area. 295 */ 296struct vmcb_segment * 297vmcb_seg(struct vmcb *vmcb, int type) 298{ 299 struct vmcb_state *state; 300 struct vmcb_segment *seg; 301 302 state = &vmcb->state; 303 304 switch (type) { 305 case VM_REG_GUEST_CS: 306 seg = &state->cs; 307 break; 308 309 case VM_REG_GUEST_DS: 310 seg = &state->ds; 311 break; 312 313 case VM_REG_GUEST_ES: 314 seg = &state->es; 315 break; 316 317 case VM_REG_GUEST_FS: 318 seg = &state->fs; 319 break; 320 321 case VM_REG_GUEST_GS: 322 seg = &state->gs; 323 break; 324 325 case VM_REG_GUEST_SS: 326 seg = &state->ss; 327 break; 328 329 case VM_REG_GUEST_GDTR: 330 seg = &state->gdt; 331 break; 332 333 case VM_REG_GUEST_IDTR: 334 seg = &state->idt; 335 break; 336 337 case VM_REG_GUEST_LDTR: 338 seg = &state->ldt; 339 break; 340 341 case VM_REG_GUEST_TR: 342 seg = &state->tr; 343 break; 344 345 default: 346 seg = NULL; 347 break; 348 } 349 350 return (seg); 351} 352 353/* 354 * Inject an event to vcpu as described in section 15.20, "Event injection". 355 */ 356int 357vmcb_eventinject(struct vmcb_ctrl *ctrl, int type, int vector, 358 uint32_t error, boolean_t ec_valid) 359{ 360 int intr_type; 361 362 static uint8_t svm_intr_type_map[VM_EVENT_MAX] = { 363 -1, /* VM_EVENT_NONE */ 364 VMCB_EVENTINJ_TYPE_INTR, /* VM_HW_INTR */ 365 VMCB_EVENTINJ_TYPE_NMI, /* VM_NMI */ 366 VMCB_EVENTINJ_TYPE_EXCEPTION, /* VM_HW_EXCEPTION */ 367 VMCB_EVENTINJ_TYPE_INTn, /* VM_SW_INTR, INT */ 368 VMCB_EVENTINJ_TYPE_INTn, /* VM_PRIV_SW_EXCEPTION */ 369 VMCB_EVENTINJ_TYPE_INTn, /* VM_SW_EXCEPTION */ 370 }; 371 372 intr_type = svm_intr_type_map[type]; 373 if (intr_type < VMCB_EVENTINJ_TYPE_INTR || 374 intr_type > VMCB_EVENTINJ_TYPE_INTn) { 375 ERR("Event:%d is not supported by SVM.\n", type); 376 return (EINVAL); 377 } 378 379 if (intr_type == VMCB_EVENTINJ_TYPE_EXCEPTION && vector == IDT_NMI) { 380 ERR("NMI with Exception type is not possible.\n"); 381 return (EINVAL); 382 } 383 384 ctrl->eventinj = (vector & VMCB_EVENTINJ_VECTOR_MASK) | 385 (intr_type << VMCB_EVENTINJ_INTR_TYPE_SHIFT) | 386 (ec_valid ? VMCB_EVENTINJ_EC_VALID : 0) | 387 VMCB_EVENTINJ_VALID; 388 389 ctrl->eventinj |= (uint64_t)error << VMCB_EVENTINJ_ERRCODE_SHIFT; 390 391 return (0); 392} 393