1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AMD Secure Encrypted Virtualization (SEV) interface 4 * 5 * Copyright (C) 2016,2019 Advanced Micro Devices, Inc. 6 * 7 * Author: Brijesh Singh <brijesh.singh@amd.com> 8 */ 9 10 #include <linux/bitfield.h> 11 #include <linux/module.h> 12 #include <linux/kernel.h> 13 #include <linux/kthread.h> 14 #include <linux/sched.h> 15 #include <linux/interrupt.h> 16 #include <linux/spinlock.h> 17 #include <linux/spinlock_types.h> 18 #include <linux/types.h> 19 #include <linux/mutex.h> 20 #include <linux/delay.h> 21 #include <linux/hw_random.h> 22 #include <linux/ccp.h> 23 #include <linux/firmware.h> 24 #include <linux/panic_notifier.h> 25 #include <linux/gfp.h> 26 #include <linux/cpufeature.h> 27 #include <linux/fs.h> 28 #include <linux/fs_struct.h> 29 #include <linux/psp.h> 30 #include <linux/amd-iommu.h> 31 32 #include <asm/smp.h> 33 #include <asm/cacheflush.h> 34 #include <asm/e820/types.h> 35 #include <asm/sev.h> 36 37 #include "psp-dev.h" 38 #include "sev-dev.h" 39 40 #define DEVICE_NAME "sev" 41 #define SEV_FW_FILE "amd/sev.fw" 42 #define SEV_FW_NAME_SIZE 64 43 44 /* Minimum firmware version required for the SEV-SNP support */ 45 #define SNP_MIN_API_MAJOR 1 46 #define SNP_MIN_API_MINOR 51 47 48 /* 49 * Maximum number of firmware-writable buffers that might be specified 50 * in the parameters of a legacy SEV command buffer. 51 */ 52 #define CMD_BUF_FW_WRITABLE_MAX 2 53 54 /* Leave room in the descriptor array for an end-of-list indicator. */ 55 #define CMD_BUF_DESC_MAX (CMD_BUF_FW_WRITABLE_MAX + 1) 56 57 static DEFINE_MUTEX(sev_cmd_mutex); 58 static struct sev_misc_dev *misc_dev; 59 60 static int psp_cmd_timeout = 100; 61 module_param(psp_cmd_timeout, int, 0644); 62 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands"); 63 64 static int psp_probe_timeout = 5; 65 module_param(psp_probe_timeout, int, 0644); 66 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe"); 67 68 static char *init_ex_path; 69 module_param(init_ex_path, charp, 0444); 70 MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX"); 71 72 static bool psp_init_on_probe = true; 73 module_param(psp_init_on_probe, bool, 0444); 74 MODULE_PARM_DESC(psp_init_on_probe, " if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it"); 75 76 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */ 77 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */ 78 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */ 79 MODULE_FIRMWARE("amd/amd_sev_fam19h_model1xh.sbin"); /* 4th gen EPYC */ 80 81 static bool psp_dead; 82 static int psp_timeout; 83 84 /* Trusted Memory Region (TMR): 85 * The TMR is a 1MB area that must be 1MB aligned. Use the page allocator 86 * to allocate the memory, which will return aligned memory for the specified 87 * allocation order. 88 * 89 * When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB sized. 90 */ 91 #define SEV_TMR_SIZE (1024 * 1024) 92 #define SNP_TMR_SIZE (2 * 1024 * 1024) 93 94 static void *sev_es_tmr; 95 static size_t sev_es_tmr_size = SEV_TMR_SIZE; 96 97 /* INIT_EX NV Storage: 98 * The NV Storage is a 32Kb area and must be 4Kb page aligned. Use the page 99 * allocator to allocate the memory, which will return aligned memory for the 100 * specified allocation order. 101 */ 102 #define NV_LENGTH (32 * 1024) 103 static void *sev_init_ex_buffer; 104 105 /* 106 * SEV_DATA_RANGE_LIST: 107 * Array containing range of pages that firmware transitions to HV-fixed 108 * page state. 109 */ 110 static struct sev_data_range_list *snp_range_list; 111 112 static inline bool sev_version_greater_or_equal(u8 maj, u8 min) 113 { 114 struct sev_device *sev = psp_master->sev_data; 115 116 if (sev->api_major > maj) 117 return true; 118 119 if (sev->api_major == maj && sev->api_minor >= min) 120 return true; 121 122 return false; 123 } 124 125 static void sev_irq_handler(int irq, void *data, unsigned int status) 126 { 127 struct sev_device *sev = data; 128 int reg; 129 130 /* Check if it is command completion: */ 131 if (!(status & SEV_CMD_COMPLETE)) 132 return; 133 134 /* Check if it is SEV command completion: */ 135 reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 136 if (FIELD_GET(PSP_CMDRESP_RESP, reg)) { 137 sev->int_rcvd = 1; 138 wake_up(&sev->int_queue); 139 } 140 } 141 142 static int sev_wait_cmd_ioc(struct sev_device *sev, 143 unsigned int *reg, unsigned int timeout) 144 { 145 int ret; 146 147 /* 148 * If invoked during panic handling, local interrupts are disabled, 149 * so the PSP command completion interrupt can't be used. Poll for 150 * PSP command completion instead. 151 */ 152 if (irqs_disabled()) { 153 unsigned long timeout_usecs = (timeout * USEC_PER_SEC) / 10; 154 155 /* Poll for SEV command completion: */ 156 while (timeout_usecs--) { 157 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 158 if (*reg & PSP_CMDRESP_RESP) 159 return 0; 160 161 udelay(10); 162 } 163 return -ETIMEDOUT; 164 } 165 166 ret = wait_event_timeout(sev->int_queue, 167 sev->int_rcvd, timeout * HZ); 168 if (!ret) 169 return -ETIMEDOUT; 170 171 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 172 173 return 0; 174 } 175 176 static int sev_cmd_buffer_len(int cmd) 177 { 178 switch (cmd) { 179 case SEV_CMD_INIT: return sizeof(struct sev_data_init); 180 case SEV_CMD_INIT_EX: return sizeof(struct sev_data_init_ex); 181 case SEV_CMD_SNP_SHUTDOWN_EX: return sizeof(struct sev_data_snp_shutdown_ex); 182 case SEV_CMD_SNP_INIT_EX: return sizeof(struct sev_data_snp_init_ex); 183 case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status); 184 case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr); 185 case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import); 186 case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export); 187 case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start); 188 case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data); 189 case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa); 190 case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish); 191 case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure); 192 case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate); 193 case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate); 194 case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission); 195 case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status); 196 case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg); 197 case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg); 198 case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start); 199 case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data); 200 case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa); 201 case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish); 202 case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start); 203 case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish); 204 case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data); 205 case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa); 206 case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret); 207 case SEV_CMD_DOWNLOAD_FIRMWARE: return sizeof(struct sev_data_download_firmware); 208 case SEV_CMD_GET_ID: return sizeof(struct sev_data_get_id); 209 case SEV_CMD_ATTESTATION_REPORT: return sizeof(struct sev_data_attestation_report); 210 case SEV_CMD_SEND_CANCEL: return sizeof(struct sev_data_send_cancel); 211 case SEV_CMD_SNP_GCTX_CREATE: return sizeof(struct sev_data_snp_addr); 212 case SEV_CMD_SNP_LAUNCH_START: return sizeof(struct sev_data_snp_launch_start); 213 case SEV_CMD_SNP_LAUNCH_UPDATE: return sizeof(struct sev_data_snp_launch_update); 214 case SEV_CMD_SNP_ACTIVATE: return sizeof(struct sev_data_snp_activate); 215 case SEV_CMD_SNP_DECOMMISSION: return sizeof(struct sev_data_snp_addr); 216 case SEV_CMD_SNP_PAGE_RECLAIM: return sizeof(struct sev_data_snp_page_reclaim); 217 case SEV_CMD_SNP_GUEST_STATUS: return sizeof(struct sev_data_snp_guest_status); 218 case SEV_CMD_SNP_LAUNCH_FINISH: return sizeof(struct sev_data_snp_launch_finish); 219 case SEV_CMD_SNP_DBG_DECRYPT: return sizeof(struct sev_data_snp_dbg); 220 case SEV_CMD_SNP_DBG_ENCRYPT: return sizeof(struct sev_data_snp_dbg); 221 case SEV_CMD_SNP_PAGE_UNSMASH: return sizeof(struct sev_data_snp_page_unsmash); 222 case SEV_CMD_SNP_PLATFORM_STATUS: return sizeof(struct sev_data_snp_addr); 223 case SEV_CMD_SNP_GUEST_REQUEST: return sizeof(struct sev_data_snp_guest_request); 224 case SEV_CMD_SNP_CONFIG: return sizeof(struct sev_user_data_snp_config); 225 case SEV_CMD_SNP_COMMIT: return sizeof(struct sev_data_snp_commit); 226 default: return 0; 227 } 228 229 return 0; 230 } 231 232 static struct file *open_file_as_root(const char *filename, int flags, umode_t mode) 233 { 234 struct file *fp; 235 struct path root; 236 struct cred *cred; 237 const struct cred *old_cred; 238 239 task_lock(&init_task); 240 get_fs_root(init_task.fs, &root); 241 task_unlock(&init_task); 242 243 cred = prepare_creds(); 244 if (!cred) 245 return ERR_PTR(-ENOMEM); 246 cred->fsuid = GLOBAL_ROOT_UID; 247 old_cred = override_creds(cred); 248 249 fp = file_open_root(&root, filename, flags, mode); 250 path_put(&root); 251 252 revert_creds(old_cred); 253 254 return fp; 255 } 256 257 static int sev_read_init_ex_file(void) 258 { 259 struct sev_device *sev = psp_master->sev_data; 260 struct file *fp; 261 ssize_t nread; 262 263 lockdep_assert_held(&sev_cmd_mutex); 264 265 if (!sev_init_ex_buffer) 266 return -EOPNOTSUPP; 267 268 fp = open_file_as_root(init_ex_path, O_RDONLY, 0); 269 if (IS_ERR(fp)) { 270 int ret = PTR_ERR(fp); 271 272 if (ret == -ENOENT) { 273 dev_info(sev->dev, 274 "SEV: %s does not exist and will be created later.\n", 275 init_ex_path); 276 ret = 0; 277 } else { 278 dev_err(sev->dev, 279 "SEV: could not open %s for read, error %d\n", 280 init_ex_path, ret); 281 } 282 return ret; 283 } 284 285 nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL); 286 if (nread != NV_LENGTH) { 287 dev_info(sev->dev, 288 "SEV: could not read %u bytes to non volatile memory area, ret %ld\n", 289 NV_LENGTH, nread); 290 } 291 292 dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread); 293 filp_close(fp, NULL); 294 295 return 0; 296 } 297 298 static int sev_write_init_ex_file(void) 299 { 300 struct sev_device *sev = psp_master->sev_data; 301 struct file *fp; 302 loff_t offset = 0; 303 ssize_t nwrite; 304 305 lockdep_assert_held(&sev_cmd_mutex); 306 307 if (!sev_init_ex_buffer) 308 return 0; 309 310 fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600); 311 if (IS_ERR(fp)) { 312 int ret = PTR_ERR(fp); 313 314 dev_err(sev->dev, 315 "SEV: could not open file for write, error %d\n", 316 ret); 317 return ret; 318 } 319 320 nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset); 321 vfs_fsync(fp, 0); 322 filp_close(fp, NULL); 323 324 if (nwrite != NV_LENGTH) { 325 dev_err(sev->dev, 326 "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n", 327 NV_LENGTH, nwrite); 328 return -EIO; 329 } 330 331 dev_dbg(sev->dev, "SEV: write successful to NV file\n"); 332 333 return 0; 334 } 335 336 static int sev_write_init_ex_file_if_required(int cmd_id) 337 { 338 lockdep_assert_held(&sev_cmd_mutex); 339 340 if (!sev_init_ex_buffer) 341 return 0; 342 343 /* 344 * Only a few platform commands modify the SPI/NV area, but none of the 345 * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN, 346 * PEK_CERT_IMPORT, and PDH_GEN do. 347 */ 348 switch (cmd_id) { 349 case SEV_CMD_FACTORY_RESET: 350 case SEV_CMD_INIT_EX: 351 case SEV_CMD_PDH_GEN: 352 case SEV_CMD_PEK_CERT_IMPORT: 353 case SEV_CMD_PEK_GEN: 354 break; 355 default: 356 return 0; 357 } 358 359 return sev_write_init_ex_file(); 360 } 361 362 /* 363 * snp_reclaim_pages() needs __sev_do_cmd_locked(), and __sev_do_cmd_locked() 364 * needs snp_reclaim_pages(), so a forward declaration is needed. 365 */ 366 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret); 367 368 static int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked) 369 { 370 int ret, err, i; 371 372 paddr = __sme_clr(ALIGN_DOWN(paddr, PAGE_SIZE)); 373 374 for (i = 0; i < npages; i++, paddr += PAGE_SIZE) { 375 struct sev_data_snp_page_reclaim data = {0}; 376 377 data.paddr = paddr; 378 379 if (locked) 380 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); 381 else 382 ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); 383 384 if (ret) 385 goto cleanup; 386 387 ret = rmp_make_shared(__phys_to_pfn(paddr), PG_LEVEL_4K); 388 if (ret) 389 goto cleanup; 390 } 391 392 return 0; 393 394 cleanup: 395 /* 396 * If there was a failure reclaiming the page then it is no longer safe 397 * to release it back to the system; leak it instead. 398 */ 399 snp_leak_pages(__phys_to_pfn(paddr), npages - i); 400 return ret; 401 } 402 403 static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked) 404 { 405 unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT; 406 int rc, i; 407 408 for (i = 0; i < npages; i++, pfn++) { 409 rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true); 410 if (rc) 411 goto cleanup; 412 } 413 414 return 0; 415 416 cleanup: 417 /* 418 * Try unrolling the firmware state changes by 419 * reclaiming the pages which were already changed to the 420 * firmware state. 421 */ 422 snp_reclaim_pages(paddr, i, locked); 423 424 return rc; 425 } 426 427 static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order) 428 { 429 unsigned long npages = 1ul << order, paddr; 430 struct sev_device *sev; 431 struct page *page; 432 433 if (!psp_master || !psp_master->sev_data) 434 return NULL; 435 436 page = alloc_pages(gfp_mask, order); 437 if (!page) 438 return NULL; 439 440 /* If SEV-SNP is initialized then add the page in RMP table. */ 441 sev = psp_master->sev_data; 442 if (!sev->snp_initialized) 443 return page; 444 445 paddr = __pa((unsigned long)page_address(page)); 446 if (rmp_mark_pages_firmware(paddr, npages, false)) 447 return NULL; 448 449 return page; 450 } 451 452 void *snp_alloc_firmware_page(gfp_t gfp_mask) 453 { 454 struct page *page; 455 456 page = __snp_alloc_firmware_pages(gfp_mask, 0); 457 458 return page ? page_address(page) : NULL; 459 } 460 EXPORT_SYMBOL_GPL(snp_alloc_firmware_page); 461 462 static void __snp_free_firmware_pages(struct page *page, int order, bool locked) 463 { 464 struct sev_device *sev = psp_master->sev_data; 465 unsigned long paddr, npages = 1ul << order; 466 467 if (!page) 468 return; 469 470 paddr = __pa((unsigned long)page_address(page)); 471 if (sev->snp_initialized && 472 snp_reclaim_pages(paddr, npages, locked)) 473 return; 474 475 __free_pages(page, order); 476 } 477 478 void snp_free_firmware_page(void *addr) 479 { 480 if (!addr) 481 return; 482 483 __snp_free_firmware_pages(virt_to_page(addr), 0, false); 484 } 485 EXPORT_SYMBOL_GPL(snp_free_firmware_page); 486 487 static void *sev_fw_alloc(unsigned long len) 488 { 489 struct page *page; 490 491 page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len)); 492 if (!page) 493 return NULL; 494 495 return page_address(page); 496 } 497 498 /** 499 * struct cmd_buf_desc - descriptors for managing legacy SEV command address 500 * parameters corresponding to buffers that may be written to by firmware. 501 * 502 * @paddr_ptr: pointer to the address parameter in the command buffer which may 503 * need to be saved/restored depending on whether a bounce buffer 504 * is used. In the case of a bounce buffer, the command buffer 505 * needs to be updated with the address of the new bounce buffer 506 * snp_map_cmd_buf_desc() has allocated specifically for it. Must 507 * be NULL if this descriptor is only an end-of-list indicator. 508 * 509 * @paddr_orig: storage for the original address parameter, which can be used to 510 * restore the original value in @paddr_ptr in cases where it is 511 * replaced with the address of a bounce buffer. 512 * 513 * @len: length of buffer located at the address originally stored at @paddr_ptr 514 * 515 * @guest_owned: true if the address corresponds to guest-owned pages, in which 516 * case bounce buffers are not needed. 517 */ 518 struct cmd_buf_desc { 519 u64 *paddr_ptr; 520 u64 paddr_orig; 521 u32 len; 522 bool guest_owned; 523 }; 524 525 /* 526 * If a legacy SEV command parameter is a memory address, those pages in 527 * turn need to be transitioned to/from firmware-owned before/after 528 * executing the firmware command. 529 * 530 * Additionally, in cases where those pages are not guest-owned, a bounce 531 * buffer is needed in place of the original memory address parameter. 532 * 533 * A set of descriptors are used to keep track of this handling, and 534 * initialized here based on the specific commands being executed. 535 */ 536 static void snp_populate_cmd_buf_desc_list(int cmd, void *cmd_buf, 537 struct cmd_buf_desc *desc_list) 538 { 539 switch (cmd) { 540 case SEV_CMD_PDH_CERT_EXPORT: { 541 struct sev_data_pdh_cert_export *data = cmd_buf; 542 543 desc_list[0].paddr_ptr = &data->pdh_cert_address; 544 desc_list[0].len = data->pdh_cert_len; 545 desc_list[1].paddr_ptr = &data->cert_chain_address; 546 desc_list[1].len = data->cert_chain_len; 547 break; 548 } 549 case SEV_CMD_GET_ID: { 550 struct sev_data_get_id *data = cmd_buf; 551 552 desc_list[0].paddr_ptr = &data->address; 553 desc_list[0].len = data->len; 554 break; 555 } 556 case SEV_CMD_PEK_CSR: { 557 struct sev_data_pek_csr *data = cmd_buf; 558 559 desc_list[0].paddr_ptr = &data->address; 560 desc_list[0].len = data->len; 561 break; 562 } 563 case SEV_CMD_LAUNCH_UPDATE_DATA: { 564 struct sev_data_launch_update_data *data = cmd_buf; 565 566 desc_list[0].paddr_ptr = &data->address; 567 desc_list[0].len = data->len; 568 desc_list[0].guest_owned = true; 569 break; 570 } 571 case SEV_CMD_LAUNCH_UPDATE_VMSA: { 572 struct sev_data_launch_update_vmsa *data = cmd_buf; 573 574 desc_list[0].paddr_ptr = &data->address; 575 desc_list[0].len = data->len; 576 desc_list[0].guest_owned = true; 577 break; 578 } 579 case SEV_CMD_LAUNCH_MEASURE: { 580 struct sev_data_launch_measure *data = cmd_buf; 581 582 desc_list[0].paddr_ptr = &data->address; 583 desc_list[0].len = data->len; 584 break; 585 } 586 case SEV_CMD_LAUNCH_UPDATE_SECRET: { 587 struct sev_data_launch_secret *data = cmd_buf; 588 589 desc_list[0].paddr_ptr = &data->guest_address; 590 desc_list[0].len = data->guest_len; 591 desc_list[0].guest_owned = true; 592 break; 593 } 594 case SEV_CMD_DBG_DECRYPT: { 595 struct sev_data_dbg *data = cmd_buf; 596 597 desc_list[0].paddr_ptr = &data->dst_addr; 598 desc_list[0].len = data->len; 599 desc_list[0].guest_owned = true; 600 break; 601 } 602 case SEV_CMD_DBG_ENCRYPT: { 603 struct sev_data_dbg *data = cmd_buf; 604 605 desc_list[0].paddr_ptr = &data->dst_addr; 606 desc_list[0].len = data->len; 607 desc_list[0].guest_owned = true; 608 break; 609 } 610 case SEV_CMD_ATTESTATION_REPORT: { 611 struct sev_data_attestation_report *data = cmd_buf; 612 613 desc_list[0].paddr_ptr = &data->address; 614 desc_list[0].len = data->len; 615 break; 616 } 617 case SEV_CMD_SEND_START: { 618 struct sev_data_send_start *data = cmd_buf; 619 620 desc_list[0].paddr_ptr = &data->session_address; 621 desc_list[0].len = data->session_len; 622 break; 623 } 624 case SEV_CMD_SEND_UPDATE_DATA: { 625 struct sev_data_send_update_data *data = cmd_buf; 626 627 desc_list[0].paddr_ptr = &data->hdr_address; 628 desc_list[0].len = data->hdr_len; 629 desc_list[1].paddr_ptr = &data->trans_address; 630 desc_list[1].len = data->trans_len; 631 break; 632 } 633 case SEV_CMD_SEND_UPDATE_VMSA: { 634 struct sev_data_send_update_vmsa *data = cmd_buf; 635 636 desc_list[0].paddr_ptr = &data->hdr_address; 637 desc_list[0].len = data->hdr_len; 638 desc_list[1].paddr_ptr = &data->trans_address; 639 desc_list[1].len = data->trans_len; 640 break; 641 } 642 case SEV_CMD_RECEIVE_UPDATE_DATA: { 643 struct sev_data_receive_update_data *data = cmd_buf; 644 645 desc_list[0].paddr_ptr = &data->guest_address; 646 desc_list[0].len = data->guest_len; 647 desc_list[0].guest_owned = true; 648 break; 649 } 650 case SEV_CMD_RECEIVE_UPDATE_VMSA: { 651 struct sev_data_receive_update_vmsa *data = cmd_buf; 652 653 desc_list[0].paddr_ptr = &data->guest_address; 654 desc_list[0].len = data->guest_len; 655 desc_list[0].guest_owned = true; 656 break; 657 } 658 default: 659 break; 660 } 661 } 662 663 static int snp_map_cmd_buf_desc(struct cmd_buf_desc *desc) 664 { 665 unsigned int npages; 666 667 if (!desc->len) 668 return 0; 669 670 /* Allocate a bounce buffer if this isn't a guest owned page. */ 671 if (!desc->guest_owned) { 672 struct page *page; 673 674 page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(desc->len)); 675 if (!page) { 676 pr_warn("Failed to allocate bounce buffer for SEV legacy command.\n"); 677 return -ENOMEM; 678 } 679 680 desc->paddr_orig = *desc->paddr_ptr; 681 *desc->paddr_ptr = __psp_pa(page_to_virt(page)); 682 } 683 684 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT; 685 686 /* Transition the buffer to firmware-owned. */ 687 if (rmp_mark_pages_firmware(*desc->paddr_ptr, npages, true)) { 688 pr_warn("Error moving pages to firmware-owned state for SEV legacy command.\n"); 689 return -EFAULT; 690 } 691 692 return 0; 693 } 694 695 static int snp_unmap_cmd_buf_desc(struct cmd_buf_desc *desc) 696 { 697 unsigned int npages; 698 699 if (!desc->len) 700 return 0; 701 702 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT; 703 704 /* Transition the buffers back to hypervisor-owned. */ 705 if (snp_reclaim_pages(*desc->paddr_ptr, npages, true)) { 706 pr_warn("Failed to reclaim firmware-owned pages while issuing SEV legacy command.\n"); 707 return -EFAULT; 708 } 709 710 /* Copy data from bounce buffer and then free it. */ 711 if (!desc->guest_owned) { 712 void *bounce_buf = __va(__sme_clr(*desc->paddr_ptr)); 713 void *dst_buf = __va(__sme_clr(desc->paddr_orig)); 714 715 memcpy(dst_buf, bounce_buf, desc->len); 716 __free_pages(virt_to_page(bounce_buf), get_order(desc->len)); 717 718 /* Restore the original address in the command buffer. */ 719 *desc->paddr_ptr = desc->paddr_orig; 720 } 721 722 return 0; 723 } 724 725 static int snp_map_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) 726 { 727 int i; 728 729 snp_populate_cmd_buf_desc_list(cmd, cmd_buf, desc_list); 730 731 for (i = 0; i < CMD_BUF_DESC_MAX; i++) { 732 struct cmd_buf_desc *desc = &desc_list[i]; 733 734 if (!desc->paddr_ptr) 735 break; 736 737 if (snp_map_cmd_buf_desc(desc)) 738 goto err_unmap; 739 } 740 741 return 0; 742 743 err_unmap: 744 for (i--; i >= 0; i--) 745 snp_unmap_cmd_buf_desc(&desc_list[i]); 746 747 return -EFAULT; 748 } 749 750 static int snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc *desc_list) 751 { 752 int i, ret = 0; 753 754 for (i = 0; i < CMD_BUF_DESC_MAX; i++) { 755 struct cmd_buf_desc *desc = &desc_list[i]; 756 757 if (!desc->paddr_ptr) 758 break; 759 760 if (snp_unmap_cmd_buf_desc(&desc_list[i])) 761 ret = -EFAULT; 762 } 763 764 return ret; 765 } 766 767 static bool sev_cmd_buf_writable(int cmd) 768 { 769 switch (cmd) { 770 case SEV_CMD_PLATFORM_STATUS: 771 case SEV_CMD_GUEST_STATUS: 772 case SEV_CMD_LAUNCH_START: 773 case SEV_CMD_RECEIVE_START: 774 case SEV_CMD_LAUNCH_MEASURE: 775 case SEV_CMD_SEND_START: 776 case SEV_CMD_SEND_UPDATE_DATA: 777 case SEV_CMD_SEND_UPDATE_VMSA: 778 case SEV_CMD_PEK_CSR: 779 case SEV_CMD_PDH_CERT_EXPORT: 780 case SEV_CMD_GET_ID: 781 case SEV_CMD_ATTESTATION_REPORT: 782 return true; 783 default: 784 return false; 785 } 786 } 787 788 /* After SNP is INIT'ed, the behavior of legacy SEV commands is changed. */ 789 static bool snp_legacy_handling_needed(int cmd) 790 { 791 struct sev_device *sev = psp_master->sev_data; 792 793 return cmd < SEV_CMD_SNP_INIT && sev->snp_initialized; 794 } 795 796 static int snp_prep_cmd_buf(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) 797 { 798 if (!snp_legacy_handling_needed(cmd)) 799 return 0; 800 801 if (snp_map_cmd_buf_desc_list(cmd, cmd_buf, desc_list)) 802 return -EFAULT; 803 804 /* 805 * Before command execution, the command buffer needs to be put into 806 * the firmware-owned state. 807 */ 808 if (sev_cmd_buf_writable(cmd)) { 809 if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true)) 810 return -EFAULT; 811 } 812 813 return 0; 814 } 815 816 static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf) 817 { 818 if (!snp_legacy_handling_needed(cmd)) 819 return 0; 820 821 /* 822 * After command completion, the command buffer needs to be put back 823 * into the hypervisor-owned state. 824 */ 825 if (sev_cmd_buf_writable(cmd)) 826 if (snp_reclaim_pages(__pa(cmd_buf), 1, true)) 827 return -EFAULT; 828 829 return 0; 830 } 831 832 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) 833 { 834 struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0}; 835 struct psp_device *psp = psp_master; 836 struct sev_device *sev; 837 unsigned int cmdbuff_hi, cmdbuff_lo; 838 unsigned int phys_lsb, phys_msb; 839 unsigned int reg, ret = 0; 840 void *cmd_buf; 841 int buf_len; 842 843 if (!psp || !psp->sev_data) 844 return -ENODEV; 845 846 if (psp_dead) 847 return -EBUSY; 848 849 sev = psp->sev_data; 850 851 buf_len = sev_cmd_buffer_len(cmd); 852 if (WARN_ON_ONCE(!data != !buf_len)) 853 return -EINVAL; 854 855 /* 856 * Copy the incoming data to driver's scratch buffer as __pa() will not 857 * work for some memory, e.g. vmalloc'd addresses, and @data may not be 858 * physically contiguous. 859 */ 860 if (data) { 861 /* 862 * Commands are generally issued one at a time and require the 863 * sev_cmd_mutex, but there could be recursive firmware requests 864 * due to SEV_CMD_SNP_PAGE_RECLAIM needing to be issued while 865 * preparing buffers for another command. This is the only known 866 * case of nesting in the current code, so exactly one 867 * additional command buffer is available for that purpose. 868 */ 869 if (!sev->cmd_buf_active) { 870 cmd_buf = sev->cmd_buf; 871 sev->cmd_buf_active = true; 872 } else if (!sev->cmd_buf_backup_active) { 873 cmd_buf = sev->cmd_buf_backup; 874 sev->cmd_buf_backup_active = true; 875 } else { 876 dev_err(sev->dev, 877 "SEV: too many firmware commands in progress, no command buffers available.\n"); 878 return -EBUSY; 879 } 880 881 memcpy(cmd_buf, data, buf_len); 882 883 /* 884 * The behavior of the SEV-legacy commands is altered when the 885 * SNP firmware is in the INIT state. 886 */ 887 ret = snp_prep_cmd_buf(cmd, cmd_buf, desc_list); 888 if (ret) { 889 dev_err(sev->dev, 890 "SEV: failed to prepare buffer for legacy command 0x%x. Error: %d\n", 891 cmd, ret); 892 return ret; 893 } 894 } else { 895 cmd_buf = sev->cmd_buf; 896 } 897 898 /* Get the physical address of the command buffer */ 899 phys_lsb = data ? lower_32_bits(__psp_pa(cmd_buf)) : 0; 900 phys_msb = data ? upper_32_bits(__psp_pa(cmd_buf)) : 0; 901 902 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n", 903 cmd, phys_msb, phys_lsb, psp_timeout); 904 905 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data, 906 buf_len, false); 907 908 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 909 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 910 911 sev->int_rcvd = 0; 912 913 reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd) | SEV_CMDRESP_IOC; 914 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg); 915 916 /* wait for command completion */ 917 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout); 918 if (ret) { 919 if (psp_ret) 920 *psp_ret = 0; 921 922 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd); 923 psp_dead = true; 924 925 return ret; 926 } 927 928 psp_timeout = psp_cmd_timeout; 929 930 if (psp_ret) 931 *psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg); 932 933 if (FIELD_GET(PSP_CMDRESP_STS, reg)) { 934 dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n", 935 cmd, FIELD_GET(PSP_CMDRESP_STS, reg)); 936 937 /* 938 * PSP firmware may report additional error information in the 939 * command buffer registers on error. Print contents of command 940 * buffer registers if they changed. 941 */ 942 cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 943 cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 944 if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) { 945 dev_dbg(sev->dev, "Additional error information reported in cmdbuff:"); 946 dev_dbg(sev->dev, " cmdbuff hi: %#010x\n", cmdbuff_hi); 947 dev_dbg(sev->dev, " cmdbuff lo: %#010x\n", cmdbuff_lo); 948 } 949 ret = -EIO; 950 } else { 951 ret = sev_write_init_ex_file_if_required(cmd); 952 } 953 954 /* 955 * Copy potential output from the PSP back to data. Do this even on 956 * failure in case the caller wants to glean something from the error. 957 */ 958 if (data) { 959 int ret_reclaim; 960 /* 961 * Restore the page state after the command completes. 962 */ 963 ret_reclaim = snp_reclaim_cmd_buf(cmd, cmd_buf); 964 if (ret_reclaim) { 965 dev_err(sev->dev, 966 "SEV: failed to reclaim buffer for legacy command %#x. Error: %d\n", 967 cmd, ret_reclaim); 968 return ret_reclaim; 969 } 970 971 memcpy(data, cmd_buf, buf_len); 972 973 if (sev->cmd_buf_backup_active) 974 sev->cmd_buf_backup_active = false; 975 else 976 sev->cmd_buf_active = false; 977 978 if (snp_unmap_cmd_buf_desc_list(desc_list)) 979 return -EFAULT; 980 } 981 982 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, 983 buf_len, false); 984 985 return ret; 986 } 987 988 int sev_do_cmd(int cmd, void *data, int *psp_ret) 989 { 990 int rc; 991 992 mutex_lock(&sev_cmd_mutex); 993 rc = __sev_do_cmd_locked(cmd, data, psp_ret); 994 mutex_unlock(&sev_cmd_mutex); 995 996 return rc; 997 } 998 EXPORT_SYMBOL_GPL(sev_do_cmd); 999 1000 static int __sev_init_locked(int *error) 1001 { 1002 struct sev_data_init data; 1003 1004 memset(&data, 0, sizeof(data)); 1005 if (sev_es_tmr) { 1006 /* 1007 * Do not include the encryption mask on the physical 1008 * address of the TMR (firmware should clear it anyway). 1009 */ 1010 data.tmr_address = __pa(sev_es_tmr); 1011 1012 data.flags |= SEV_INIT_FLAGS_SEV_ES; 1013 data.tmr_len = sev_es_tmr_size; 1014 } 1015 1016 return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); 1017 } 1018 1019 static int __sev_init_ex_locked(int *error) 1020 { 1021 struct sev_data_init_ex data; 1022 1023 memset(&data, 0, sizeof(data)); 1024 data.length = sizeof(data); 1025 data.nv_address = __psp_pa(sev_init_ex_buffer); 1026 data.nv_len = NV_LENGTH; 1027 1028 if (sev_es_tmr) { 1029 /* 1030 * Do not include the encryption mask on the physical 1031 * address of the TMR (firmware should clear it anyway). 1032 */ 1033 data.tmr_address = __pa(sev_es_tmr); 1034 1035 data.flags |= SEV_INIT_FLAGS_SEV_ES; 1036 data.tmr_len = sev_es_tmr_size; 1037 } 1038 1039 return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error); 1040 } 1041 1042 static inline int __sev_do_init_locked(int *psp_ret) 1043 { 1044 if (sev_init_ex_buffer) 1045 return __sev_init_ex_locked(psp_ret); 1046 else 1047 return __sev_init_locked(psp_ret); 1048 } 1049 1050 static void snp_set_hsave_pa(void *arg) 1051 { 1052 wrmsrl(MSR_VM_HSAVE_PA, 0); 1053 } 1054 1055 static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg) 1056 { 1057 struct sev_data_range_list *range_list = arg; 1058 struct sev_data_range *range = &range_list->ranges[range_list->num_elements]; 1059 size_t size; 1060 1061 /* 1062 * Ensure the list of HV_FIXED pages that will be passed to firmware 1063 * do not exceed the page-sized argument buffer. 1064 */ 1065 if ((range_list->num_elements * sizeof(struct sev_data_range) + 1066 sizeof(struct sev_data_range_list)) > PAGE_SIZE) 1067 return -E2BIG; 1068 1069 switch (rs->desc) { 1070 case E820_TYPE_RESERVED: 1071 case E820_TYPE_PMEM: 1072 case E820_TYPE_ACPI: 1073 range->base = rs->start & PAGE_MASK; 1074 size = PAGE_ALIGN((rs->end + 1) - rs->start); 1075 range->page_count = size >> PAGE_SHIFT; 1076 range_list->num_elements++; 1077 break; 1078 default: 1079 break; 1080 } 1081 1082 return 0; 1083 } 1084 1085 static int __sev_snp_init_locked(int *error) 1086 { 1087 struct psp_device *psp = psp_master; 1088 struct sev_data_snp_init_ex data; 1089 struct sev_device *sev; 1090 void *arg = &data; 1091 int cmd, rc = 0; 1092 1093 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) 1094 return -ENODEV; 1095 1096 sev = psp->sev_data; 1097 1098 if (sev->snp_initialized) 1099 return 0; 1100 1101 if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) { 1102 dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n", 1103 SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR); 1104 return 0; 1105 } 1106 1107 /* SNP_INIT requires MSR_VM_HSAVE_PA to be cleared on all CPUs. */ 1108 on_each_cpu(snp_set_hsave_pa, NULL, 1); 1109 1110 /* 1111 * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list 1112 * of system physical address ranges to convert into HV-fixed page 1113 * states during the RMP initialization. For instance, the memory that 1114 * UEFI reserves should be included in the that list. This allows system 1115 * components that occasionally write to memory (e.g. logging to UEFI 1116 * reserved regions) to not fail due to RMP initialization and SNP 1117 * enablement. 1118 * 1119 */ 1120 if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) { 1121 /* 1122 * Firmware checks that the pages containing the ranges enumerated 1123 * in the RANGES structure are either in the default page state or in the 1124 * firmware page state. 1125 */ 1126 snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL); 1127 if (!snp_range_list) { 1128 dev_err(sev->dev, 1129 "SEV: SNP_INIT_EX range list memory allocation failed\n"); 1130 return -ENOMEM; 1131 } 1132 1133 /* 1134 * Retrieve all reserved memory regions from the e820 memory map 1135 * to be setup as HV-fixed pages. 1136 */ 1137 rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0, 1138 snp_range_list, snp_filter_reserved_mem_regions); 1139 if (rc) { 1140 dev_err(sev->dev, 1141 "SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc); 1142 return rc; 1143 } 1144 1145 memset(&data, 0, sizeof(data)); 1146 data.init_rmp = 1; 1147 data.list_paddr_en = 1; 1148 data.list_paddr = __psp_pa(snp_range_list); 1149 cmd = SEV_CMD_SNP_INIT_EX; 1150 } else { 1151 cmd = SEV_CMD_SNP_INIT; 1152 arg = NULL; 1153 } 1154 1155 /* 1156 * The following sequence must be issued before launching the first SNP 1157 * guest to ensure all dirty cache lines are flushed, including from 1158 * updates to the RMP table itself via the RMPUPDATE instruction: 1159 * 1160 * - WBINVD on all running CPUs 1161 * - SEV_CMD_SNP_INIT[_EX] firmware command 1162 * - WBINVD on all running CPUs 1163 * - SEV_CMD_SNP_DF_FLUSH firmware command 1164 */ 1165 wbinvd_on_all_cpus(); 1166 1167 rc = __sev_do_cmd_locked(cmd, arg, error); 1168 if (rc) 1169 return rc; 1170 1171 /* Prepare for first SNP guest launch after INIT. */ 1172 wbinvd_on_all_cpus(); 1173 rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error); 1174 if (rc) 1175 return rc; 1176 1177 sev->snp_initialized = true; 1178 dev_dbg(sev->dev, "SEV-SNP firmware initialized\n"); 1179 1180 sev_es_tmr_size = SNP_TMR_SIZE; 1181 1182 return rc; 1183 } 1184 1185 static void __sev_platform_init_handle_tmr(struct sev_device *sev) 1186 { 1187 if (sev_es_tmr) 1188 return; 1189 1190 /* Obtain the TMR memory area for SEV-ES use */ 1191 sev_es_tmr = sev_fw_alloc(sev_es_tmr_size); 1192 if (sev_es_tmr) { 1193 /* Must flush the cache before giving it to the firmware */ 1194 if (!sev->snp_initialized) 1195 clflush_cache_range(sev_es_tmr, sev_es_tmr_size); 1196 } else { 1197 dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n"); 1198 } 1199 } 1200 1201 /* 1202 * If an init_ex_path is provided allocate a buffer for the file and 1203 * read in the contents. Additionally, if SNP is initialized, convert 1204 * the buffer pages to firmware pages. 1205 */ 1206 static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev) 1207 { 1208 struct page *page; 1209 int rc; 1210 1211 if (!init_ex_path) 1212 return 0; 1213 1214 if (sev_init_ex_buffer) 1215 return 0; 1216 1217 page = alloc_pages(GFP_KERNEL, get_order(NV_LENGTH)); 1218 if (!page) { 1219 dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n"); 1220 return -ENOMEM; 1221 } 1222 1223 sev_init_ex_buffer = page_address(page); 1224 1225 rc = sev_read_init_ex_file(); 1226 if (rc) 1227 return rc; 1228 1229 /* If SEV-SNP is initialized, transition to firmware page. */ 1230 if (sev->snp_initialized) { 1231 unsigned long npages; 1232 1233 npages = 1UL << get_order(NV_LENGTH); 1234 if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, false)) { 1235 dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n"); 1236 return -ENOMEM; 1237 } 1238 } 1239 1240 return 0; 1241 } 1242 1243 static int __sev_platform_init_locked(int *error) 1244 { 1245 int rc, psp_ret = SEV_RET_NO_FW_CALL; 1246 struct sev_device *sev; 1247 1248 if (!psp_master || !psp_master->sev_data) 1249 return -ENODEV; 1250 1251 sev = psp_master->sev_data; 1252 1253 if (sev->state == SEV_STATE_INIT) 1254 return 0; 1255 1256 __sev_platform_init_handle_tmr(sev); 1257 1258 rc = __sev_platform_init_handle_init_ex_path(sev); 1259 if (rc) 1260 return rc; 1261 1262 rc = __sev_do_init_locked(&psp_ret); 1263 if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) { 1264 /* 1265 * Initialization command returned an integrity check failure 1266 * status code, meaning that firmware load and validation of SEV 1267 * related persistent data has failed. Retrying the 1268 * initialization function should succeed by replacing the state 1269 * with a reset state. 1270 */ 1271 dev_err(sev->dev, 1272 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state."); 1273 rc = __sev_do_init_locked(&psp_ret); 1274 } 1275 1276 if (error) 1277 *error = psp_ret; 1278 1279 if (rc) 1280 return rc; 1281 1282 sev->state = SEV_STATE_INIT; 1283 1284 /* Prepare for first SEV guest launch after INIT */ 1285 wbinvd_on_all_cpus(); 1286 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error); 1287 if (rc) 1288 return rc; 1289 1290 dev_dbg(sev->dev, "SEV firmware initialized\n"); 1291 1292 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major, 1293 sev->api_minor, sev->build); 1294 1295 return 0; 1296 } 1297 1298 static int _sev_platform_init_locked(struct sev_platform_init_args *args) 1299 { 1300 struct sev_device *sev; 1301 int rc; 1302 1303 if (!psp_master || !psp_master->sev_data) 1304 return -ENODEV; 1305 1306 sev = psp_master->sev_data; 1307 1308 if (sev->state == SEV_STATE_INIT) 1309 return 0; 1310 1311 /* 1312 * Legacy guests cannot be running while SNP_INIT(_EX) is executing, 1313 * so perform SEV-SNP initialization at probe time. 1314 */ 1315 rc = __sev_snp_init_locked(&args->error); 1316 if (rc && rc != -ENODEV) { 1317 /* 1318 * Don't abort the probe if SNP INIT failed, 1319 * continue to initialize the legacy SEV firmware. 1320 */ 1321 dev_err(sev->dev, "SEV-SNP: failed to INIT rc %d, error %#x\n", 1322 rc, args->error); 1323 } 1324 1325 /* Defer legacy SEV/SEV-ES support if allowed by caller/module. */ 1326 if (args->probe && !psp_init_on_probe) 1327 return 0; 1328 1329 return __sev_platform_init_locked(&args->error); 1330 } 1331 1332 int sev_platform_init(struct sev_platform_init_args *args) 1333 { 1334 int rc; 1335 1336 mutex_lock(&sev_cmd_mutex); 1337 rc = _sev_platform_init_locked(args); 1338 mutex_unlock(&sev_cmd_mutex); 1339 1340 return rc; 1341 } 1342 EXPORT_SYMBOL_GPL(sev_platform_init); 1343 1344 static int __sev_platform_shutdown_locked(int *error) 1345 { 1346 struct psp_device *psp = psp_master; 1347 struct sev_device *sev; 1348 int ret; 1349 1350 if (!psp || !psp->sev_data) 1351 return 0; 1352 1353 sev = psp->sev_data; 1354 1355 if (sev->state == SEV_STATE_UNINIT) 1356 return 0; 1357 1358 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error); 1359 if (ret) 1360 return ret; 1361 1362 sev->state = SEV_STATE_UNINIT; 1363 dev_dbg(sev->dev, "SEV firmware shutdown\n"); 1364 1365 return ret; 1366 } 1367 1368 static int sev_get_platform_state(int *state, int *error) 1369 { 1370 struct sev_user_data_status data; 1371 int rc; 1372 1373 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error); 1374 if (rc) 1375 return rc; 1376 1377 *state = data.state; 1378 return rc; 1379 } 1380 1381 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable) 1382 { 1383 int state, rc; 1384 1385 if (!writable) 1386 return -EPERM; 1387 1388 /* 1389 * The SEV spec requires that FACTORY_RESET must be issued in 1390 * UNINIT state. Before we go further lets check if any guest is 1391 * active. 1392 * 1393 * If FW is in WORKING state then deny the request otherwise issue 1394 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET. 1395 * 1396 */ 1397 rc = sev_get_platform_state(&state, &argp->error); 1398 if (rc) 1399 return rc; 1400 1401 if (state == SEV_STATE_WORKING) 1402 return -EBUSY; 1403 1404 if (state == SEV_STATE_INIT) { 1405 rc = __sev_platform_shutdown_locked(&argp->error); 1406 if (rc) 1407 return rc; 1408 } 1409 1410 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error); 1411 } 1412 1413 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp) 1414 { 1415 struct sev_user_data_status data; 1416 int ret; 1417 1418 memset(&data, 0, sizeof(data)); 1419 1420 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error); 1421 if (ret) 1422 return ret; 1423 1424 if (copy_to_user((void __user *)argp->data, &data, sizeof(data))) 1425 ret = -EFAULT; 1426 1427 return ret; 1428 } 1429 1430 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable) 1431 { 1432 struct sev_device *sev = psp_master->sev_data; 1433 int rc; 1434 1435 if (!writable) 1436 return -EPERM; 1437 1438 if (sev->state == SEV_STATE_UNINIT) { 1439 rc = __sev_platform_init_locked(&argp->error); 1440 if (rc) 1441 return rc; 1442 } 1443 1444 return __sev_do_cmd_locked(cmd, NULL, &argp->error); 1445 } 1446 1447 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable) 1448 { 1449 struct sev_device *sev = psp_master->sev_data; 1450 struct sev_user_data_pek_csr input; 1451 struct sev_data_pek_csr data; 1452 void __user *input_address; 1453 void *blob = NULL; 1454 int ret; 1455 1456 if (!writable) 1457 return -EPERM; 1458 1459 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 1460 return -EFAULT; 1461 1462 memset(&data, 0, sizeof(data)); 1463 1464 /* userspace wants to query CSR length */ 1465 if (!input.address || !input.length) 1466 goto cmd; 1467 1468 /* allocate a physically contiguous buffer to store the CSR blob */ 1469 input_address = (void __user *)input.address; 1470 if (input.length > SEV_FW_BLOB_MAX_SIZE) 1471 return -EFAULT; 1472 1473 blob = kzalloc(input.length, GFP_KERNEL); 1474 if (!blob) 1475 return -ENOMEM; 1476 1477 data.address = __psp_pa(blob); 1478 data.len = input.length; 1479 1480 cmd: 1481 if (sev->state == SEV_STATE_UNINIT) { 1482 ret = __sev_platform_init_locked(&argp->error); 1483 if (ret) 1484 goto e_free_blob; 1485 } 1486 1487 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error); 1488 1489 /* If we query the CSR length, FW responded with expected data. */ 1490 input.length = data.len; 1491 1492 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 1493 ret = -EFAULT; 1494 goto e_free_blob; 1495 } 1496 1497 if (blob) { 1498 if (copy_to_user(input_address, blob, input.length)) 1499 ret = -EFAULT; 1500 } 1501 1502 e_free_blob: 1503 kfree(blob); 1504 return ret; 1505 } 1506 1507 void *psp_copy_user_blob(u64 uaddr, u32 len) 1508 { 1509 if (!uaddr || !len) 1510 return ERR_PTR(-EINVAL); 1511 1512 /* verify that blob length does not exceed our limit */ 1513 if (len > SEV_FW_BLOB_MAX_SIZE) 1514 return ERR_PTR(-EINVAL); 1515 1516 return memdup_user((void __user *)uaddr, len); 1517 } 1518 EXPORT_SYMBOL_GPL(psp_copy_user_blob); 1519 1520 static int sev_get_api_version(void) 1521 { 1522 struct sev_device *sev = psp_master->sev_data; 1523 struct sev_user_data_status status; 1524 int error = 0, ret; 1525 1526 ret = sev_platform_status(&status, &error); 1527 if (ret) { 1528 dev_err(sev->dev, 1529 "SEV: failed to get status. Error: %#x\n", error); 1530 return 1; 1531 } 1532 1533 sev->api_major = status.api_major; 1534 sev->api_minor = status.api_minor; 1535 sev->build = status.build; 1536 sev->state = status.state; 1537 1538 return 0; 1539 } 1540 1541 static int sev_get_firmware(struct device *dev, 1542 const struct firmware **firmware) 1543 { 1544 char fw_name_specific[SEV_FW_NAME_SIZE]; 1545 char fw_name_subset[SEV_FW_NAME_SIZE]; 1546 1547 snprintf(fw_name_specific, sizeof(fw_name_specific), 1548 "amd/amd_sev_fam%.2xh_model%.2xh.sbin", 1549 boot_cpu_data.x86, boot_cpu_data.x86_model); 1550 1551 snprintf(fw_name_subset, sizeof(fw_name_subset), 1552 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin", 1553 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4); 1554 1555 /* Check for SEV FW for a particular model. 1556 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h 1557 * 1558 * or 1559 * 1560 * Check for SEV FW common to a subset of models. 1561 * Ex. amd_sev_fam17h_model0xh.sbin for 1562 * Family 17h Model 00h -- Family 17h Model 0Fh 1563 * 1564 * or 1565 * 1566 * Fall-back to using generic name: sev.fw 1567 */ 1568 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) || 1569 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) || 1570 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0)) 1571 return 0; 1572 1573 return -ENOENT; 1574 } 1575 1576 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */ 1577 static int sev_update_firmware(struct device *dev) 1578 { 1579 struct sev_data_download_firmware *data; 1580 const struct firmware *firmware; 1581 int ret, error, order; 1582 struct page *p; 1583 u64 data_size; 1584 1585 if (!sev_version_greater_or_equal(0, 15)) { 1586 dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n"); 1587 return -1; 1588 } 1589 1590 if (sev_get_firmware(dev, &firmware) == -ENOENT) { 1591 dev_dbg(dev, "No SEV firmware file present\n"); 1592 return -1; 1593 } 1594 1595 /* 1596 * SEV FW expects the physical address given to it to be 32 1597 * byte aligned. Memory allocated has structure placed at the 1598 * beginning followed by the firmware being passed to the SEV 1599 * FW. Allocate enough memory for data structure + alignment 1600 * padding + SEV FW. 1601 */ 1602 data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32); 1603 1604 order = get_order(firmware->size + data_size); 1605 p = alloc_pages(GFP_KERNEL, order); 1606 if (!p) { 1607 ret = -1; 1608 goto fw_err; 1609 } 1610 1611 /* 1612 * Copy firmware data to a kernel allocated contiguous 1613 * memory region. 1614 */ 1615 data = page_address(p); 1616 memcpy(page_address(p) + data_size, firmware->data, firmware->size); 1617 1618 data->address = __psp_pa(page_address(p) + data_size); 1619 data->len = firmware->size; 1620 1621 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); 1622 1623 /* 1624 * A quirk for fixing the committed TCB version, when upgrading from 1625 * earlier firmware version than 1.50. 1626 */ 1627 if (!ret && !sev_version_greater_or_equal(1, 50)) 1628 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); 1629 1630 if (ret) 1631 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error); 1632 else 1633 dev_info(dev, "SEV firmware update successful\n"); 1634 1635 __free_pages(p, order); 1636 1637 fw_err: 1638 release_firmware(firmware); 1639 1640 return ret; 1641 } 1642 1643 static int __sev_snp_shutdown_locked(int *error, bool panic) 1644 { 1645 struct sev_device *sev = psp_master->sev_data; 1646 struct sev_data_snp_shutdown_ex data; 1647 int ret; 1648 1649 if (!sev->snp_initialized) 1650 return 0; 1651 1652 memset(&data, 0, sizeof(data)); 1653 data.len = sizeof(data); 1654 data.iommu_snp_shutdown = 1; 1655 1656 /* 1657 * If invoked during panic handling, local interrupts are disabled 1658 * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called. 1659 * In that case, a wbinvd() is done on remote CPUs via the NMI 1660 * callback, so only a local wbinvd() is needed here. 1661 */ 1662 if (!panic) 1663 wbinvd_on_all_cpus(); 1664 else 1665 wbinvd(); 1666 1667 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error); 1668 /* SHUTDOWN may require DF_FLUSH */ 1669 if (*error == SEV_RET_DFFLUSH_REQUIRED) { 1670 ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, NULL); 1671 if (ret) { 1672 dev_err(sev->dev, "SEV-SNP DF_FLUSH failed\n"); 1673 return ret; 1674 } 1675 /* reissue the shutdown command */ 1676 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, 1677 error); 1678 } 1679 if (ret) { 1680 dev_err(sev->dev, "SEV-SNP firmware shutdown failed\n"); 1681 return ret; 1682 } 1683 1684 /* 1685 * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP 1686 * enforcement by the IOMMU and also transitions all pages 1687 * associated with the IOMMU to the Reclaim state. 1688 * Firmware was transitioning the IOMMU pages to Hypervisor state 1689 * before version 1.53. But, accounting for the number of assigned 1690 * 4kB pages in a 2M page was done incorrectly by not transitioning 1691 * to the Reclaim state. This resulted in RMP #PF when later accessing 1692 * the 2M page containing those pages during kexec boot. Hence, the 1693 * firmware now transitions these pages to Reclaim state and hypervisor 1694 * needs to transition these pages to shared state. SNP Firmware 1695 * version 1.53 and above are needed for kexec boot. 1696 */ 1697 ret = amd_iommu_snp_disable(); 1698 if (ret) { 1699 dev_err(sev->dev, "SNP IOMMU shutdown failed\n"); 1700 return ret; 1701 } 1702 1703 sev->snp_initialized = false; 1704 dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n"); 1705 1706 return ret; 1707 } 1708 1709 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable) 1710 { 1711 struct sev_device *sev = psp_master->sev_data; 1712 struct sev_user_data_pek_cert_import input; 1713 struct sev_data_pek_cert_import data; 1714 void *pek_blob, *oca_blob; 1715 int ret; 1716 1717 if (!writable) 1718 return -EPERM; 1719 1720 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 1721 return -EFAULT; 1722 1723 /* copy PEK certificate blobs from userspace */ 1724 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len); 1725 if (IS_ERR(pek_blob)) 1726 return PTR_ERR(pek_blob); 1727 1728 data.reserved = 0; 1729 data.pek_cert_address = __psp_pa(pek_blob); 1730 data.pek_cert_len = input.pek_cert_len; 1731 1732 /* copy PEK certificate blobs from userspace */ 1733 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len); 1734 if (IS_ERR(oca_blob)) { 1735 ret = PTR_ERR(oca_blob); 1736 goto e_free_pek; 1737 } 1738 1739 data.oca_cert_address = __psp_pa(oca_blob); 1740 data.oca_cert_len = input.oca_cert_len; 1741 1742 /* If platform is not in INIT state then transition it to INIT */ 1743 if (sev->state != SEV_STATE_INIT) { 1744 ret = __sev_platform_init_locked(&argp->error); 1745 if (ret) 1746 goto e_free_oca; 1747 } 1748 1749 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error); 1750 1751 e_free_oca: 1752 kfree(oca_blob); 1753 e_free_pek: 1754 kfree(pek_blob); 1755 return ret; 1756 } 1757 1758 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp) 1759 { 1760 struct sev_user_data_get_id2 input; 1761 struct sev_data_get_id data; 1762 void __user *input_address; 1763 void *id_blob = NULL; 1764 int ret; 1765 1766 /* SEV GET_ID is available from SEV API v0.16 and up */ 1767 if (!sev_version_greater_or_equal(0, 16)) 1768 return -ENOTSUPP; 1769 1770 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 1771 return -EFAULT; 1772 1773 input_address = (void __user *)input.address; 1774 1775 if (input.address && input.length) { 1776 /* 1777 * The length of the ID shouldn't be assumed by software since 1778 * it may change in the future. The allocation size is limited 1779 * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator. 1780 * If the allocation fails, simply return ENOMEM rather than 1781 * warning in the kernel log. 1782 */ 1783 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN); 1784 if (!id_blob) 1785 return -ENOMEM; 1786 1787 data.address = __psp_pa(id_blob); 1788 data.len = input.length; 1789 } else { 1790 data.address = 0; 1791 data.len = 0; 1792 } 1793 1794 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error); 1795 1796 /* 1797 * Firmware will return the length of the ID value (either the minimum 1798 * required length or the actual length written), return it to the user. 1799 */ 1800 input.length = data.len; 1801 1802 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 1803 ret = -EFAULT; 1804 goto e_free; 1805 } 1806 1807 if (id_blob) { 1808 if (copy_to_user(input_address, id_blob, data.len)) { 1809 ret = -EFAULT; 1810 goto e_free; 1811 } 1812 } 1813 1814 e_free: 1815 kfree(id_blob); 1816 1817 return ret; 1818 } 1819 1820 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp) 1821 { 1822 struct sev_data_get_id *data; 1823 u64 data_size, user_size; 1824 void *id_blob, *mem; 1825 int ret; 1826 1827 /* SEV GET_ID available from SEV API v0.16 and up */ 1828 if (!sev_version_greater_or_equal(0, 16)) 1829 return -ENOTSUPP; 1830 1831 /* SEV FW expects the buffer it fills with the ID to be 1832 * 8-byte aligned. Memory allocated should be enough to 1833 * hold data structure + alignment padding + memory 1834 * where SEV FW writes the ID. 1835 */ 1836 data_size = ALIGN(sizeof(struct sev_data_get_id), 8); 1837 user_size = sizeof(struct sev_user_data_get_id); 1838 1839 mem = kzalloc(data_size + user_size, GFP_KERNEL); 1840 if (!mem) 1841 return -ENOMEM; 1842 1843 data = mem; 1844 id_blob = mem + data_size; 1845 1846 data->address = __psp_pa(id_blob); 1847 data->len = user_size; 1848 1849 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error); 1850 if (!ret) { 1851 if (copy_to_user((void __user *)argp->data, id_blob, data->len)) 1852 ret = -EFAULT; 1853 } 1854 1855 kfree(mem); 1856 1857 return ret; 1858 } 1859 1860 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable) 1861 { 1862 struct sev_device *sev = psp_master->sev_data; 1863 struct sev_user_data_pdh_cert_export input; 1864 void *pdh_blob = NULL, *cert_blob = NULL; 1865 struct sev_data_pdh_cert_export data; 1866 void __user *input_cert_chain_address; 1867 void __user *input_pdh_cert_address; 1868 int ret; 1869 1870 /* If platform is not in INIT state then transition it to INIT. */ 1871 if (sev->state != SEV_STATE_INIT) { 1872 if (!writable) 1873 return -EPERM; 1874 1875 ret = __sev_platform_init_locked(&argp->error); 1876 if (ret) 1877 return ret; 1878 } 1879 1880 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 1881 return -EFAULT; 1882 1883 memset(&data, 0, sizeof(data)); 1884 1885 /* Userspace wants to query the certificate length. */ 1886 if (!input.pdh_cert_address || 1887 !input.pdh_cert_len || 1888 !input.cert_chain_address) 1889 goto cmd; 1890 1891 input_pdh_cert_address = (void __user *)input.pdh_cert_address; 1892 input_cert_chain_address = (void __user *)input.cert_chain_address; 1893 1894 /* Allocate a physically contiguous buffer to store the PDH blob. */ 1895 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) 1896 return -EFAULT; 1897 1898 /* Allocate a physically contiguous buffer to store the cert chain blob. */ 1899 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) 1900 return -EFAULT; 1901 1902 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL); 1903 if (!pdh_blob) 1904 return -ENOMEM; 1905 1906 data.pdh_cert_address = __psp_pa(pdh_blob); 1907 data.pdh_cert_len = input.pdh_cert_len; 1908 1909 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL); 1910 if (!cert_blob) { 1911 ret = -ENOMEM; 1912 goto e_free_pdh; 1913 } 1914 1915 data.cert_chain_address = __psp_pa(cert_blob); 1916 data.cert_chain_len = input.cert_chain_len; 1917 1918 cmd: 1919 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error); 1920 1921 /* If we query the length, FW responded with expected data. */ 1922 input.cert_chain_len = data.cert_chain_len; 1923 input.pdh_cert_len = data.pdh_cert_len; 1924 1925 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 1926 ret = -EFAULT; 1927 goto e_free_cert; 1928 } 1929 1930 if (pdh_blob) { 1931 if (copy_to_user(input_pdh_cert_address, 1932 pdh_blob, input.pdh_cert_len)) { 1933 ret = -EFAULT; 1934 goto e_free_cert; 1935 } 1936 } 1937 1938 if (cert_blob) { 1939 if (copy_to_user(input_cert_chain_address, 1940 cert_blob, input.cert_chain_len)) 1941 ret = -EFAULT; 1942 } 1943 1944 e_free_cert: 1945 kfree(cert_blob); 1946 e_free_pdh: 1947 kfree(pdh_blob); 1948 return ret; 1949 } 1950 1951 static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp) 1952 { 1953 struct sev_device *sev = psp_master->sev_data; 1954 struct sev_data_snp_addr buf; 1955 struct page *status_page; 1956 void *data; 1957 int ret; 1958 1959 if (!sev->snp_initialized || !argp->data) 1960 return -EINVAL; 1961 1962 status_page = alloc_page(GFP_KERNEL_ACCOUNT); 1963 if (!status_page) 1964 return -ENOMEM; 1965 1966 data = page_address(status_page); 1967 1968 /* 1969 * Firmware expects status page to be in firmware-owned state, otherwise 1970 * it will report firmware error code INVALID_PAGE_STATE (0x1A). 1971 */ 1972 if (rmp_mark_pages_firmware(__pa(data), 1, true)) { 1973 ret = -EFAULT; 1974 goto cleanup; 1975 } 1976 1977 buf.address = __psp_pa(data); 1978 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error); 1979 1980 /* 1981 * Status page will be transitioned to Reclaim state upon success, or 1982 * left in Firmware state in failure. Use snp_reclaim_pages() to 1983 * transition either case back to Hypervisor-owned state. 1984 */ 1985 if (snp_reclaim_pages(__pa(data), 1, true)) 1986 return -EFAULT; 1987 1988 if (ret) 1989 goto cleanup; 1990 1991 if (copy_to_user((void __user *)argp->data, data, 1992 sizeof(struct sev_user_data_snp_status))) 1993 ret = -EFAULT; 1994 1995 cleanup: 1996 __free_pages(status_page, 0); 1997 return ret; 1998 } 1999 2000 static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp) 2001 { 2002 struct sev_device *sev = psp_master->sev_data; 2003 struct sev_data_snp_commit buf; 2004 2005 if (!sev->snp_initialized) 2006 return -EINVAL; 2007 2008 buf.len = sizeof(buf); 2009 2010 return __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error); 2011 } 2012 2013 static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable) 2014 { 2015 struct sev_device *sev = psp_master->sev_data; 2016 struct sev_user_data_snp_config config; 2017 2018 if (!sev->snp_initialized || !argp->data) 2019 return -EINVAL; 2020 2021 if (!writable) 2022 return -EPERM; 2023 2024 if (copy_from_user(&config, (void __user *)argp->data, sizeof(config))) 2025 return -EFAULT; 2026 2027 return __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error); 2028 } 2029 2030 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) 2031 { 2032 void __user *argp = (void __user *)arg; 2033 struct sev_issue_cmd input; 2034 int ret = -EFAULT; 2035 bool writable = file->f_mode & FMODE_WRITE; 2036 2037 if (!psp_master || !psp_master->sev_data) 2038 return -ENODEV; 2039 2040 if (ioctl != SEV_ISSUE_CMD) 2041 return -EINVAL; 2042 2043 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd))) 2044 return -EFAULT; 2045 2046 if (input.cmd > SEV_MAX) 2047 return -EINVAL; 2048 2049 mutex_lock(&sev_cmd_mutex); 2050 2051 switch (input.cmd) { 2052 2053 case SEV_FACTORY_RESET: 2054 ret = sev_ioctl_do_reset(&input, writable); 2055 break; 2056 case SEV_PLATFORM_STATUS: 2057 ret = sev_ioctl_do_platform_status(&input); 2058 break; 2059 case SEV_PEK_GEN: 2060 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable); 2061 break; 2062 case SEV_PDH_GEN: 2063 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable); 2064 break; 2065 case SEV_PEK_CSR: 2066 ret = sev_ioctl_do_pek_csr(&input, writable); 2067 break; 2068 case SEV_PEK_CERT_IMPORT: 2069 ret = sev_ioctl_do_pek_import(&input, writable); 2070 break; 2071 case SEV_PDH_CERT_EXPORT: 2072 ret = sev_ioctl_do_pdh_export(&input, writable); 2073 break; 2074 case SEV_GET_ID: 2075 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n"); 2076 ret = sev_ioctl_do_get_id(&input); 2077 break; 2078 case SEV_GET_ID2: 2079 ret = sev_ioctl_do_get_id2(&input); 2080 break; 2081 case SNP_PLATFORM_STATUS: 2082 ret = sev_ioctl_do_snp_platform_status(&input); 2083 break; 2084 case SNP_COMMIT: 2085 ret = sev_ioctl_do_snp_commit(&input); 2086 break; 2087 case SNP_SET_CONFIG: 2088 ret = sev_ioctl_do_snp_set_config(&input, writable); 2089 break; 2090 default: 2091 ret = -EINVAL; 2092 goto out; 2093 } 2094 2095 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd))) 2096 ret = -EFAULT; 2097 out: 2098 mutex_unlock(&sev_cmd_mutex); 2099 2100 return ret; 2101 } 2102 2103 static const struct file_operations sev_fops = { 2104 .owner = THIS_MODULE, 2105 .unlocked_ioctl = sev_ioctl, 2106 }; 2107 2108 int sev_platform_status(struct sev_user_data_status *data, int *error) 2109 { 2110 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error); 2111 } 2112 EXPORT_SYMBOL_GPL(sev_platform_status); 2113 2114 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error) 2115 { 2116 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error); 2117 } 2118 EXPORT_SYMBOL_GPL(sev_guest_deactivate); 2119 2120 int sev_guest_activate(struct sev_data_activate *data, int *error) 2121 { 2122 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error); 2123 } 2124 EXPORT_SYMBOL_GPL(sev_guest_activate); 2125 2126 int sev_guest_decommission(struct sev_data_decommission *data, int *error) 2127 { 2128 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error); 2129 } 2130 EXPORT_SYMBOL_GPL(sev_guest_decommission); 2131 2132 int sev_guest_df_flush(int *error) 2133 { 2134 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error); 2135 } 2136 EXPORT_SYMBOL_GPL(sev_guest_df_flush); 2137 2138 static void sev_exit(struct kref *ref) 2139 { 2140 misc_deregister(&misc_dev->misc); 2141 kfree(misc_dev); 2142 misc_dev = NULL; 2143 } 2144 2145 static int sev_misc_init(struct sev_device *sev) 2146 { 2147 struct device *dev = sev->dev; 2148 int ret; 2149 2150 /* 2151 * SEV feature support can be detected on multiple devices but the SEV 2152 * FW commands must be issued on the master. During probe, we do not 2153 * know the master hence we create /dev/sev on the first device probe. 2154 * sev_do_cmd() finds the right master device to which to issue the 2155 * command to the firmware. 2156 */ 2157 if (!misc_dev) { 2158 struct miscdevice *misc; 2159 2160 misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL); 2161 if (!misc_dev) 2162 return -ENOMEM; 2163 2164 misc = &misc_dev->misc; 2165 misc->minor = MISC_DYNAMIC_MINOR; 2166 misc->name = DEVICE_NAME; 2167 misc->fops = &sev_fops; 2168 2169 ret = misc_register(misc); 2170 if (ret) 2171 return ret; 2172 2173 kref_init(&misc_dev->refcount); 2174 } else { 2175 kref_get(&misc_dev->refcount); 2176 } 2177 2178 init_waitqueue_head(&sev->int_queue); 2179 sev->misc = misc_dev; 2180 dev_dbg(dev, "registered SEV device\n"); 2181 2182 return 0; 2183 } 2184 2185 int sev_dev_init(struct psp_device *psp) 2186 { 2187 struct device *dev = psp->dev; 2188 struct sev_device *sev; 2189 int ret = -ENOMEM; 2190 2191 if (!boot_cpu_has(X86_FEATURE_SEV)) { 2192 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n"); 2193 return 0; 2194 } 2195 2196 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL); 2197 if (!sev) 2198 goto e_err; 2199 2200 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1); 2201 if (!sev->cmd_buf) 2202 goto e_sev; 2203 2204 sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE; 2205 2206 psp->sev_data = sev; 2207 2208 sev->dev = dev; 2209 sev->psp = psp; 2210 2211 sev->io_regs = psp->io_regs; 2212 2213 sev->vdata = (struct sev_vdata *)psp->vdata->sev; 2214 if (!sev->vdata) { 2215 ret = -ENODEV; 2216 dev_err(dev, "sev: missing driver data\n"); 2217 goto e_buf; 2218 } 2219 2220 psp_set_sev_irq_handler(psp, sev_irq_handler, sev); 2221 2222 ret = sev_misc_init(sev); 2223 if (ret) 2224 goto e_irq; 2225 2226 dev_notice(dev, "sev enabled\n"); 2227 2228 return 0; 2229 2230 e_irq: 2231 psp_clear_sev_irq_handler(psp); 2232 e_buf: 2233 devm_free_pages(dev, (unsigned long)sev->cmd_buf); 2234 e_sev: 2235 devm_kfree(dev, sev); 2236 e_err: 2237 psp->sev_data = NULL; 2238 2239 dev_notice(dev, "sev initialization failed\n"); 2240 2241 return ret; 2242 } 2243 2244 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic) 2245 { 2246 int error; 2247 2248 __sev_platform_shutdown_locked(NULL); 2249 2250 if (sev_es_tmr) { 2251 /* 2252 * The TMR area was encrypted, flush it from the cache. 2253 * 2254 * If invoked during panic handling, local interrupts are 2255 * disabled and all CPUs are stopped, so wbinvd_on_all_cpus() 2256 * can't be used. In that case, wbinvd() is done on remote CPUs 2257 * via the NMI callback, and done for this CPU later during 2258 * SNP shutdown, so wbinvd_on_all_cpus() can be skipped. 2259 */ 2260 if (!panic) 2261 wbinvd_on_all_cpus(); 2262 2263 __snp_free_firmware_pages(virt_to_page(sev_es_tmr), 2264 get_order(sev_es_tmr_size), 2265 true); 2266 sev_es_tmr = NULL; 2267 } 2268 2269 if (sev_init_ex_buffer) { 2270 __snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer), 2271 get_order(NV_LENGTH), 2272 true); 2273 sev_init_ex_buffer = NULL; 2274 } 2275 2276 if (snp_range_list) { 2277 kfree(snp_range_list); 2278 snp_range_list = NULL; 2279 } 2280 2281 __sev_snp_shutdown_locked(&error, panic); 2282 } 2283 2284 static void sev_firmware_shutdown(struct sev_device *sev) 2285 { 2286 mutex_lock(&sev_cmd_mutex); 2287 __sev_firmware_shutdown(sev, false); 2288 mutex_unlock(&sev_cmd_mutex); 2289 } 2290 2291 void sev_dev_destroy(struct psp_device *psp) 2292 { 2293 struct sev_device *sev = psp->sev_data; 2294 2295 if (!sev) 2296 return; 2297 2298 sev_firmware_shutdown(sev); 2299 2300 if (sev->misc) 2301 kref_put(&misc_dev->refcount, sev_exit); 2302 2303 psp_clear_sev_irq_handler(psp); 2304 } 2305 2306 static int snp_shutdown_on_panic(struct notifier_block *nb, 2307 unsigned long reason, void *arg) 2308 { 2309 struct sev_device *sev = psp_master->sev_data; 2310 2311 /* 2312 * If sev_cmd_mutex is already acquired, then it's likely 2313 * another PSP command is in flight and issuing a shutdown 2314 * would fail in unexpected ways. Rather than create even 2315 * more confusion during a panic, just bail out here. 2316 */ 2317 if (mutex_is_locked(&sev_cmd_mutex)) 2318 return NOTIFY_DONE; 2319 2320 __sev_firmware_shutdown(sev, true); 2321 2322 return NOTIFY_DONE; 2323 } 2324 2325 static struct notifier_block snp_panic_notifier = { 2326 .notifier_call = snp_shutdown_on_panic, 2327 }; 2328 2329 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd, 2330 void *data, int *error) 2331 { 2332 if (!filep || filep->f_op != &sev_fops) 2333 return -EBADF; 2334 2335 return sev_do_cmd(cmd, data, error); 2336 } 2337 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user); 2338 2339 void sev_pci_init(void) 2340 { 2341 struct sev_device *sev = psp_master->sev_data; 2342 struct sev_platform_init_args args = {0}; 2343 int rc; 2344 2345 if (!sev) 2346 return; 2347 2348 psp_timeout = psp_probe_timeout; 2349 2350 if (sev_get_api_version()) 2351 goto err; 2352 2353 if (sev_update_firmware(sev->dev) == 0) 2354 sev_get_api_version(); 2355 2356 /* Initialize the platform */ 2357 args.probe = true; 2358 rc = sev_platform_init(&args); 2359 if (rc) 2360 dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n", 2361 args.error, rc); 2362 2363 dev_info(sev->dev, "SEV%s API:%d.%d build:%d\n", sev->snp_initialized ? 2364 "-SNP" : "", sev->api_major, sev->api_minor, sev->build); 2365 2366 atomic_notifier_chain_register(&panic_notifier_list, 2367 &snp_panic_notifier); 2368 return; 2369 2370 err: 2371 psp_master->sev_data = NULL; 2372 } 2373 2374 void sev_pci_exit(void) 2375 { 2376 struct sev_device *sev = psp_master->sev_data; 2377 2378 if (!sev) 2379 return; 2380 2381 sev_firmware_shutdown(sev); 2382 2383 atomic_notifier_chain_unregister(&panic_notifier_list, 2384 &snp_panic_notifier); 2385 } 2386