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 #include <linux/crash_dump.h> 32 33 #include <asm/smp.h> 34 #include <asm/cacheflush.h> 35 #include <asm/e820/types.h> 36 #include <asm/sev.h> 37 #include <asm/msr.h> 38 39 #include "psp-dev.h" 40 #include "sev-dev.h" 41 42 #define DEVICE_NAME "sev" 43 #define SEV_FW_FILE "amd/sev.fw" 44 #define SEV_FW_NAME_SIZE 64 45 46 /* Minimum firmware version required for the SEV-SNP support */ 47 #define SNP_MIN_API_MAJOR 1 48 #define SNP_MIN_API_MINOR 51 49 50 /* 51 * Maximum number of firmware-writable buffers that might be specified 52 * in the parameters of a legacy SEV command buffer. 53 */ 54 #define CMD_BUF_FW_WRITABLE_MAX 2 55 56 /* Leave room in the descriptor array for an end-of-list indicator. */ 57 #define CMD_BUF_DESC_MAX (CMD_BUF_FW_WRITABLE_MAX + 1) 58 59 static DEFINE_MUTEX(sev_cmd_mutex); 60 static struct sev_misc_dev *misc_dev; 61 62 static int psp_cmd_timeout = 100; 63 module_param(psp_cmd_timeout, int, 0644); 64 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands"); 65 66 static int psp_probe_timeout = 5; 67 module_param(psp_probe_timeout, int, 0644); 68 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe"); 69 70 static char *init_ex_path; 71 module_param(init_ex_path, charp, 0444); 72 MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX"); 73 74 static bool psp_init_on_probe = true; 75 module_param(psp_init_on_probe, bool, 0444); 76 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"); 77 78 #if IS_ENABLED(CONFIG_PCI_TSM) 79 static bool sev_tio_enabled = true; 80 module_param_named(tio, sev_tio_enabled, bool, 0444); 81 MODULE_PARM_DESC(tio, "Enables TIO in SNP_INIT_EX"); 82 #else 83 static const bool sev_tio_enabled = false; 84 #endif 85 86 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */ 87 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */ 88 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */ 89 MODULE_FIRMWARE("amd/amd_sev_fam19h_model1xh.sbin"); /* 4th gen EPYC */ 90 91 static bool psp_dead; 92 static int psp_timeout; 93 94 enum snp_hv_fixed_pages_state { 95 ALLOCATED, 96 HV_FIXED, 97 }; 98 99 struct snp_hv_fixed_pages_entry { 100 struct list_head list; 101 struct page *page; 102 unsigned int order; 103 bool free; 104 enum snp_hv_fixed_pages_state page_state; 105 }; 106 107 static LIST_HEAD(snp_hv_fixed_pages); 108 109 /* Trusted Memory Region (TMR): 110 * The TMR is a 1MB area that must be 1MB aligned. Use the page allocator 111 * to allocate the memory, which will return aligned memory for the specified 112 * allocation order. 113 * 114 * When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB sized. 115 */ 116 #define SEV_TMR_SIZE (1024 * 1024) 117 #define SNP_TMR_SIZE (2 * 1024 * 1024) 118 119 static void *sev_es_tmr; 120 static size_t sev_es_tmr_size = SEV_TMR_SIZE; 121 122 /* INIT_EX NV Storage: 123 * The NV Storage is a 32Kb area and must be 4Kb page aligned. Use the page 124 * allocator to allocate the memory, which will return aligned memory for the 125 * specified allocation order. 126 */ 127 #define NV_LENGTH (32 * 1024) 128 static void *sev_init_ex_buffer; 129 130 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic); 131 132 static int snp_shutdown_on_panic(struct notifier_block *nb, 133 unsigned long reason, void *arg); 134 135 static struct notifier_block snp_panic_notifier = { 136 .notifier_call = snp_shutdown_on_panic, 137 }; 138 139 static inline bool sev_version_greater_or_equal(u8 maj, u8 min) 140 { 141 struct sev_device *sev = psp_master->sev_data; 142 143 if (sev->api_major > maj) 144 return true; 145 146 if (sev->api_major == maj && sev->api_minor >= min) 147 return true; 148 149 return false; 150 } 151 152 static void sev_irq_handler(int irq, void *data, unsigned int status) 153 { 154 struct sev_device *sev = data; 155 int reg; 156 157 /* Check if it is command completion: */ 158 if (!(status & SEV_CMD_COMPLETE)) 159 return; 160 161 /* Check if it is SEV command completion: */ 162 reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 163 if (FIELD_GET(PSP_CMDRESP_RESP, reg)) { 164 sev->int_rcvd = 1; 165 wake_up(&sev->int_queue); 166 } 167 } 168 169 static int sev_wait_cmd_ioc(struct sev_device *sev, 170 unsigned int *reg, unsigned int timeout) 171 { 172 int ret; 173 174 /* 175 * If invoked during panic handling, local interrupts are disabled, 176 * so the PSP command completion interrupt can't be used. Poll for 177 * PSP command completion instead. 178 */ 179 if (irqs_disabled()) { 180 unsigned long timeout_usecs = (timeout * USEC_PER_SEC) / 10; 181 182 /* Poll for SEV command completion: */ 183 while (timeout_usecs--) { 184 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 185 if (*reg & PSP_CMDRESP_RESP) 186 return 0; 187 188 udelay(10); 189 } 190 return -ETIMEDOUT; 191 } 192 193 ret = wait_event_timeout(sev->int_queue, 194 sev->int_rcvd, timeout * HZ); 195 if (!ret) 196 return -ETIMEDOUT; 197 198 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 199 200 return 0; 201 } 202 203 static int sev_cmd_buffer_len(int cmd) 204 { 205 switch (cmd) { 206 case SEV_CMD_INIT: return sizeof(struct sev_data_init); 207 case SEV_CMD_INIT_EX: return sizeof(struct sev_data_init_ex); 208 case SEV_CMD_SNP_SHUTDOWN_EX: return sizeof(struct sev_data_snp_shutdown_ex); 209 case SEV_CMD_SNP_INIT_EX: return sizeof(struct sev_data_snp_init_ex); 210 case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status); 211 case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr); 212 case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import); 213 case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export); 214 case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start); 215 case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data); 216 case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa); 217 case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish); 218 case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure); 219 case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate); 220 case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate); 221 case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission); 222 case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status); 223 case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg); 224 case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg); 225 case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start); 226 case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data); 227 case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa); 228 case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish); 229 case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start); 230 case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish); 231 case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data); 232 case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa); 233 case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret); 234 case SEV_CMD_DOWNLOAD_FIRMWARE: return sizeof(struct sev_data_download_firmware); 235 case SEV_CMD_GET_ID: return sizeof(struct sev_data_get_id); 236 case SEV_CMD_ATTESTATION_REPORT: return sizeof(struct sev_data_attestation_report); 237 case SEV_CMD_SEND_CANCEL: return sizeof(struct sev_data_send_cancel); 238 case SEV_CMD_SNP_GCTX_CREATE: return sizeof(struct sev_data_snp_addr); 239 case SEV_CMD_SNP_LAUNCH_START: return sizeof(struct sev_data_snp_launch_start); 240 case SEV_CMD_SNP_LAUNCH_UPDATE: return sizeof(struct sev_data_snp_launch_update); 241 case SEV_CMD_SNP_ACTIVATE: return sizeof(struct sev_data_snp_activate); 242 case SEV_CMD_SNP_DECOMMISSION: return sizeof(struct sev_data_snp_addr); 243 case SEV_CMD_SNP_PAGE_RECLAIM: return sizeof(struct sev_data_snp_page_reclaim); 244 case SEV_CMD_SNP_GUEST_STATUS: return sizeof(struct sev_data_snp_guest_status); 245 case SEV_CMD_SNP_LAUNCH_FINISH: return sizeof(struct sev_data_snp_launch_finish); 246 case SEV_CMD_SNP_DBG_DECRYPT: return sizeof(struct sev_data_snp_dbg); 247 case SEV_CMD_SNP_DBG_ENCRYPT: return sizeof(struct sev_data_snp_dbg); 248 case SEV_CMD_SNP_PAGE_UNSMASH: return sizeof(struct sev_data_snp_page_unsmash); 249 case SEV_CMD_SNP_PLATFORM_STATUS: return sizeof(struct sev_data_snp_addr); 250 case SEV_CMD_SNP_GUEST_REQUEST: return sizeof(struct sev_data_snp_guest_request); 251 case SEV_CMD_SNP_CONFIG: return sizeof(struct sev_user_data_snp_config); 252 case SEV_CMD_SNP_COMMIT: return sizeof(struct sev_data_snp_commit); 253 case SEV_CMD_SNP_FEATURE_INFO: return sizeof(struct sev_data_snp_feature_info); 254 case SEV_CMD_SNP_VLEK_LOAD: return sizeof(struct sev_user_data_snp_vlek_load); 255 default: return sev_tio_cmd_buffer_len(cmd); 256 } 257 258 return 0; 259 } 260 261 static struct file *open_file_as_root(const char *filename, int flags, umode_t mode) 262 { 263 struct path root __free(path_put) = {}; 264 265 task_lock(&init_task); 266 get_fs_root(init_task.fs, &root); 267 task_unlock(&init_task); 268 269 CLASS(prepare_creds, cred)(); 270 if (!cred) 271 return ERR_PTR(-ENOMEM); 272 273 cred->fsuid = GLOBAL_ROOT_UID; 274 275 scoped_with_creds(cred) 276 return file_open_root(&root, filename, flags, mode); 277 } 278 279 static int sev_read_init_ex_file(void) 280 { 281 struct sev_device *sev = psp_master->sev_data; 282 struct file *fp; 283 ssize_t nread; 284 285 lockdep_assert_held(&sev_cmd_mutex); 286 287 if (!sev_init_ex_buffer) 288 return -EOPNOTSUPP; 289 290 fp = open_file_as_root(init_ex_path, O_RDONLY, 0); 291 if (IS_ERR(fp)) { 292 int ret = PTR_ERR(fp); 293 294 if (ret == -ENOENT) { 295 dev_info(sev->dev, 296 "SEV: %s does not exist and will be created later.\n", 297 init_ex_path); 298 ret = 0; 299 } else { 300 dev_err(sev->dev, 301 "SEV: could not open %s for read, error %d\n", 302 init_ex_path, ret); 303 } 304 return ret; 305 } 306 307 nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL); 308 if (nread != NV_LENGTH) { 309 dev_info(sev->dev, 310 "SEV: could not read %u bytes to non volatile memory area, ret %ld\n", 311 NV_LENGTH, nread); 312 } 313 314 dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread); 315 filp_close(fp, NULL); 316 317 return 0; 318 } 319 320 static int sev_write_init_ex_file(void) 321 { 322 struct sev_device *sev = psp_master->sev_data; 323 struct file *fp; 324 loff_t offset = 0; 325 ssize_t nwrite; 326 327 lockdep_assert_held(&sev_cmd_mutex); 328 329 if (!sev_init_ex_buffer) 330 return 0; 331 332 fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600); 333 if (IS_ERR(fp)) { 334 int ret = PTR_ERR(fp); 335 336 dev_err(sev->dev, 337 "SEV: could not open file for write, error %d\n", 338 ret); 339 return ret; 340 } 341 342 nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset); 343 vfs_fsync(fp, 0); 344 filp_close(fp, NULL); 345 346 if (nwrite != NV_LENGTH) { 347 dev_err(sev->dev, 348 "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n", 349 NV_LENGTH, nwrite); 350 return -EIO; 351 } 352 353 dev_dbg(sev->dev, "SEV: write successful to NV file\n"); 354 355 return 0; 356 } 357 358 static int sev_write_init_ex_file_if_required(int cmd_id) 359 { 360 lockdep_assert_held(&sev_cmd_mutex); 361 362 if (!sev_init_ex_buffer) 363 return 0; 364 365 /* 366 * Only a few platform commands modify the SPI/NV area, but none of the 367 * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN, 368 * PEK_CERT_IMPORT, and PDH_GEN do. 369 */ 370 switch (cmd_id) { 371 case SEV_CMD_FACTORY_RESET: 372 case SEV_CMD_INIT_EX: 373 case SEV_CMD_PDH_GEN: 374 case SEV_CMD_PEK_CERT_IMPORT: 375 case SEV_CMD_PEK_GEN: 376 break; 377 default: 378 return 0; 379 } 380 381 return sev_write_init_ex_file(); 382 } 383 384 int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked) 385 { 386 int ret, err, i; 387 388 paddr = __sme_clr(ALIGN_DOWN(paddr, PAGE_SIZE)); 389 390 for (i = 0; i < npages; i++, paddr += PAGE_SIZE) { 391 struct sev_data_snp_page_reclaim data = {0}; 392 393 data.paddr = paddr; 394 395 if (locked) 396 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); 397 else 398 ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); 399 400 if (ret) 401 goto cleanup; 402 403 ret = rmp_make_shared(__phys_to_pfn(paddr), PG_LEVEL_4K); 404 if (ret) 405 goto cleanup; 406 } 407 408 return 0; 409 410 cleanup: 411 /* 412 * If there was a failure reclaiming the page then it is no longer safe 413 * to release it back to the system; leak it instead. 414 */ 415 snp_leak_pages(__phys_to_pfn(paddr), npages - i); 416 return ret; 417 } 418 EXPORT_SYMBOL_GPL(snp_reclaim_pages); 419 420 static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked) 421 { 422 unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT; 423 int rc, i; 424 425 for (i = 0; i < npages; i++, pfn++) { 426 rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true); 427 if (rc) 428 goto cleanup; 429 } 430 431 return 0; 432 433 cleanup: 434 /* 435 * Try unrolling the firmware state changes by 436 * reclaiming the pages which were already changed to the 437 * firmware state. 438 */ 439 snp_reclaim_pages(paddr, i, locked); 440 441 return rc; 442 } 443 444 static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked) 445 { 446 unsigned long npages = 1ul << order, paddr; 447 struct sev_device *sev; 448 struct page *page; 449 450 if (!psp_master || !psp_master->sev_data) 451 return NULL; 452 453 page = alloc_pages(gfp_mask, order); 454 if (!page) 455 return NULL; 456 457 /* If SEV-SNP is initialized then add the page in RMP table. */ 458 sev = psp_master->sev_data; 459 if (!sev->snp_initialized) 460 return page; 461 462 paddr = __pa((unsigned long)page_address(page)); 463 if (rmp_mark_pages_firmware(paddr, npages, locked)) 464 return NULL; 465 466 return page; 467 } 468 469 void *snp_alloc_firmware_page(gfp_t gfp_mask) 470 { 471 struct page *page; 472 473 page = __snp_alloc_firmware_pages(gfp_mask, 0, false); 474 475 return page ? page_address(page) : NULL; 476 } 477 EXPORT_SYMBOL_GPL(snp_alloc_firmware_page); 478 479 static void __snp_free_firmware_pages(struct page *page, int order, bool locked) 480 { 481 struct sev_device *sev = psp_master->sev_data; 482 unsigned long paddr, npages = 1ul << order; 483 484 if (!page) 485 return; 486 487 paddr = __pa((unsigned long)page_address(page)); 488 if (sev->snp_initialized && 489 snp_reclaim_pages(paddr, npages, locked)) 490 return; 491 492 __free_pages(page, order); 493 } 494 495 void snp_free_firmware_page(void *addr) 496 { 497 if (!addr) 498 return; 499 500 __snp_free_firmware_pages(virt_to_page(addr), 0, false); 501 } 502 EXPORT_SYMBOL_GPL(snp_free_firmware_page); 503 504 static void *sev_fw_alloc(unsigned long len) 505 { 506 struct page *page; 507 508 page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len), true); 509 if (!page) 510 return NULL; 511 512 return page_address(page); 513 } 514 515 /** 516 * struct cmd_buf_desc - descriptors for managing legacy SEV command address 517 * parameters corresponding to buffers that may be written to by firmware. 518 * 519 * @paddr_ptr: pointer to the address parameter in the command buffer which may 520 * need to be saved/restored depending on whether a bounce buffer 521 * is used. In the case of a bounce buffer, the command buffer 522 * needs to be updated with the address of the new bounce buffer 523 * snp_map_cmd_buf_desc() has allocated specifically for it. Must 524 * be NULL if this descriptor is only an end-of-list indicator. 525 * 526 * @paddr_orig: storage for the original address parameter, which can be used to 527 * restore the original value in @paddr_ptr in cases where it is 528 * replaced with the address of a bounce buffer. 529 * 530 * @len: length of buffer located at the address originally stored at @paddr_ptr 531 * 532 * @guest_owned: true if the address corresponds to guest-owned pages, in which 533 * case bounce buffers are not needed. 534 */ 535 struct cmd_buf_desc { 536 u64 *paddr_ptr; 537 u64 paddr_orig; 538 u32 len; 539 bool guest_owned; 540 }; 541 542 /* 543 * If a legacy SEV command parameter is a memory address, those pages in 544 * turn need to be transitioned to/from firmware-owned before/after 545 * executing the firmware command. 546 * 547 * Additionally, in cases where those pages are not guest-owned, a bounce 548 * buffer is needed in place of the original memory address parameter. 549 * 550 * A set of descriptors are used to keep track of this handling, and 551 * initialized here based on the specific commands being executed. 552 */ 553 static void snp_populate_cmd_buf_desc_list(int cmd, void *cmd_buf, 554 struct cmd_buf_desc *desc_list) 555 { 556 switch (cmd) { 557 case SEV_CMD_PDH_CERT_EXPORT: { 558 struct sev_data_pdh_cert_export *data = cmd_buf; 559 560 desc_list[0].paddr_ptr = &data->pdh_cert_address; 561 desc_list[0].len = data->pdh_cert_len; 562 desc_list[1].paddr_ptr = &data->cert_chain_address; 563 desc_list[1].len = data->cert_chain_len; 564 break; 565 } 566 case SEV_CMD_GET_ID: { 567 struct sev_data_get_id *data = cmd_buf; 568 569 desc_list[0].paddr_ptr = &data->address; 570 desc_list[0].len = data->len; 571 break; 572 } 573 case SEV_CMD_PEK_CSR: { 574 struct sev_data_pek_csr *data = cmd_buf; 575 576 desc_list[0].paddr_ptr = &data->address; 577 desc_list[0].len = data->len; 578 break; 579 } 580 case SEV_CMD_LAUNCH_UPDATE_DATA: { 581 struct sev_data_launch_update_data *data = cmd_buf; 582 583 desc_list[0].paddr_ptr = &data->address; 584 desc_list[0].len = data->len; 585 desc_list[0].guest_owned = true; 586 break; 587 } 588 case SEV_CMD_LAUNCH_UPDATE_VMSA: { 589 struct sev_data_launch_update_vmsa *data = cmd_buf; 590 591 desc_list[0].paddr_ptr = &data->address; 592 desc_list[0].len = data->len; 593 desc_list[0].guest_owned = true; 594 break; 595 } 596 case SEV_CMD_LAUNCH_MEASURE: { 597 struct sev_data_launch_measure *data = cmd_buf; 598 599 desc_list[0].paddr_ptr = &data->address; 600 desc_list[0].len = data->len; 601 break; 602 } 603 case SEV_CMD_LAUNCH_UPDATE_SECRET: { 604 struct sev_data_launch_secret *data = cmd_buf; 605 606 desc_list[0].paddr_ptr = &data->guest_address; 607 desc_list[0].len = data->guest_len; 608 desc_list[0].guest_owned = true; 609 break; 610 } 611 case SEV_CMD_DBG_DECRYPT: { 612 struct sev_data_dbg *data = cmd_buf; 613 614 desc_list[0].paddr_ptr = &data->dst_addr; 615 desc_list[0].len = data->len; 616 desc_list[0].guest_owned = true; 617 break; 618 } 619 case SEV_CMD_DBG_ENCRYPT: { 620 struct sev_data_dbg *data = cmd_buf; 621 622 desc_list[0].paddr_ptr = &data->dst_addr; 623 desc_list[0].len = data->len; 624 desc_list[0].guest_owned = true; 625 break; 626 } 627 case SEV_CMD_ATTESTATION_REPORT: { 628 struct sev_data_attestation_report *data = cmd_buf; 629 630 desc_list[0].paddr_ptr = &data->address; 631 desc_list[0].len = data->len; 632 break; 633 } 634 case SEV_CMD_SEND_START: { 635 struct sev_data_send_start *data = cmd_buf; 636 637 desc_list[0].paddr_ptr = &data->session_address; 638 desc_list[0].len = data->session_len; 639 break; 640 } 641 case SEV_CMD_SEND_UPDATE_DATA: { 642 struct sev_data_send_update_data *data = cmd_buf; 643 644 desc_list[0].paddr_ptr = &data->hdr_address; 645 desc_list[0].len = data->hdr_len; 646 desc_list[1].paddr_ptr = &data->trans_address; 647 desc_list[1].len = data->trans_len; 648 break; 649 } 650 case SEV_CMD_SEND_UPDATE_VMSA: { 651 struct sev_data_send_update_vmsa *data = cmd_buf; 652 653 desc_list[0].paddr_ptr = &data->hdr_address; 654 desc_list[0].len = data->hdr_len; 655 desc_list[1].paddr_ptr = &data->trans_address; 656 desc_list[1].len = data->trans_len; 657 break; 658 } 659 case SEV_CMD_RECEIVE_UPDATE_DATA: { 660 struct sev_data_receive_update_data *data = cmd_buf; 661 662 desc_list[0].paddr_ptr = &data->guest_address; 663 desc_list[0].len = data->guest_len; 664 desc_list[0].guest_owned = true; 665 break; 666 } 667 case SEV_CMD_RECEIVE_UPDATE_VMSA: { 668 struct sev_data_receive_update_vmsa *data = cmd_buf; 669 670 desc_list[0].paddr_ptr = &data->guest_address; 671 desc_list[0].len = data->guest_len; 672 desc_list[0].guest_owned = true; 673 break; 674 } 675 default: 676 break; 677 } 678 } 679 680 static int snp_map_cmd_buf_desc(struct cmd_buf_desc *desc) 681 { 682 unsigned int npages; 683 684 if (!desc->len) 685 return 0; 686 687 /* Allocate a bounce buffer if this isn't a guest owned page. */ 688 if (!desc->guest_owned) { 689 struct page *page; 690 691 page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(desc->len)); 692 if (!page) { 693 pr_warn("Failed to allocate bounce buffer for SEV legacy command.\n"); 694 return -ENOMEM; 695 } 696 697 desc->paddr_orig = *desc->paddr_ptr; 698 *desc->paddr_ptr = __psp_pa(page_to_virt(page)); 699 } 700 701 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT; 702 703 /* Transition the buffer to firmware-owned. */ 704 if (rmp_mark_pages_firmware(*desc->paddr_ptr, npages, true)) { 705 pr_warn("Error moving pages to firmware-owned state for SEV legacy command.\n"); 706 return -EFAULT; 707 } 708 709 return 0; 710 } 711 712 static int snp_unmap_cmd_buf_desc(struct cmd_buf_desc *desc) 713 { 714 unsigned int npages; 715 716 if (!desc->len) 717 return 0; 718 719 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT; 720 721 /* Transition the buffers back to hypervisor-owned. */ 722 if (snp_reclaim_pages(*desc->paddr_ptr, npages, true)) { 723 pr_warn("Failed to reclaim firmware-owned pages while issuing SEV legacy command.\n"); 724 return -EFAULT; 725 } 726 727 /* Copy data from bounce buffer and then free it. */ 728 if (!desc->guest_owned) { 729 void *bounce_buf = __va(__sme_clr(*desc->paddr_ptr)); 730 void *dst_buf = __va(__sme_clr(desc->paddr_orig)); 731 732 memcpy(dst_buf, bounce_buf, desc->len); 733 __free_pages(virt_to_page(bounce_buf), get_order(desc->len)); 734 735 /* Restore the original address in the command buffer. */ 736 *desc->paddr_ptr = desc->paddr_orig; 737 } 738 739 return 0; 740 } 741 742 static int snp_map_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) 743 { 744 int i; 745 746 snp_populate_cmd_buf_desc_list(cmd, cmd_buf, desc_list); 747 748 for (i = 0; i < CMD_BUF_DESC_MAX; i++) { 749 struct cmd_buf_desc *desc = &desc_list[i]; 750 751 if (!desc->paddr_ptr) 752 break; 753 754 if (snp_map_cmd_buf_desc(desc)) 755 goto err_unmap; 756 } 757 758 return 0; 759 760 err_unmap: 761 for (i--; i >= 0; i--) 762 snp_unmap_cmd_buf_desc(&desc_list[i]); 763 764 return -EFAULT; 765 } 766 767 static int snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc *desc_list) 768 { 769 int i, ret = 0; 770 771 for (i = 0; i < CMD_BUF_DESC_MAX; i++) { 772 struct cmd_buf_desc *desc = &desc_list[i]; 773 774 if (!desc->paddr_ptr) 775 break; 776 777 if (snp_unmap_cmd_buf_desc(&desc_list[i])) 778 ret = -EFAULT; 779 } 780 781 return ret; 782 } 783 784 static bool sev_cmd_buf_writable(int cmd) 785 { 786 switch (cmd) { 787 case SEV_CMD_PLATFORM_STATUS: 788 case SEV_CMD_GUEST_STATUS: 789 case SEV_CMD_LAUNCH_START: 790 case SEV_CMD_RECEIVE_START: 791 case SEV_CMD_LAUNCH_MEASURE: 792 case SEV_CMD_SEND_START: 793 case SEV_CMD_SEND_UPDATE_DATA: 794 case SEV_CMD_SEND_UPDATE_VMSA: 795 case SEV_CMD_PEK_CSR: 796 case SEV_CMD_PDH_CERT_EXPORT: 797 case SEV_CMD_GET_ID: 798 case SEV_CMD_ATTESTATION_REPORT: 799 return true; 800 default: 801 return false; 802 } 803 } 804 805 /* After SNP is INIT'ed, the behavior of legacy SEV commands is changed. */ 806 static bool snp_legacy_handling_needed(int cmd) 807 { 808 struct sev_device *sev = psp_master->sev_data; 809 810 return cmd < SEV_CMD_SNP_INIT && sev->snp_initialized; 811 } 812 813 static int snp_prep_cmd_buf(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) 814 { 815 if (!snp_legacy_handling_needed(cmd)) 816 return 0; 817 818 if (snp_map_cmd_buf_desc_list(cmd, cmd_buf, desc_list)) 819 return -EFAULT; 820 821 /* 822 * Before command execution, the command buffer needs to be put into 823 * the firmware-owned state. 824 */ 825 if (sev_cmd_buf_writable(cmd)) { 826 if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true)) 827 return -EFAULT; 828 } 829 830 return 0; 831 } 832 833 static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf) 834 { 835 if (!snp_legacy_handling_needed(cmd)) 836 return 0; 837 838 /* 839 * After command completion, the command buffer needs to be put back 840 * into the hypervisor-owned state. 841 */ 842 if (sev_cmd_buf_writable(cmd)) 843 if (snp_reclaim_pages(__pa(cmd_buf), 1, true)) 844 return -EFAULT; 845 846 return 0; 847 } 848 849 int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) 850 { 851 struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0}; 852 struct psp_device *psp = psp_master; 853 struct sev_device *sev; 854 unsigned int cmdbuff_hi, cmdbuff_lo; 855 unsigned int phys_lsb, phys_msb; 856 unsigned int reg; 857 void *cmd_buf; 858 int buf_len; 859 int ret = 0; 860 861 if (!psp || !psp->sev_data) 862 return -ENODEV; 863 864 if (psp_dead) 865 return -EBUSY; 866 867 sev = psp->sev_data; 868 869 buf_len = sev_cmd_buffer_len(cmd); 870 if (WARN_ON_ONCE(!data != !buf_len)) 871 return -EINVAL; 872 873 /* 874 * Copy the incoming data to driver's scratch buffer as __pa() will not 875 * work for some memory, e.g. vmalloc'd addresses, and @data may not be 876 * physically contiguous. 877 */ 878 if (data) { 879 /* 880 * Commands are generally issued one at a time and require the 881 * sev_cmd_mutex, but there could be recursive firmware requests 882 * due to SEV_CMD_SNP_PAGE_RECLAIM needing to be issued while 883 * preparing buffers for another command. This is the only known 884 * case of nesting in the current code, so exactly one 885 * additional command buffer is available for that purpose. 886 */ 887 if (!sev->cmd_buf_active) { 888 cmd_buf = sev->cmd_buf; 889 sev->cmd_buf_active = true; 890 } else if (!sev->cmd_buf_backup_active) { 891 cmd_buf = sev->cmd_buf_backup; 892 sev->cmd_buf_backup_active = true; 893 } else { 894 dev_err(sev->dev, 895 "SEV: too many firmware commands in progress, no command buffers available.\n"); 896 return -EBUSY; 897 } 898 899 memcpy(cmd_buf, data, buf_len); 900 901 /* 902 * The behavior of the SEV-legacy commands is altered when the 903 * SNP firmware is in the INIT state. 904 */ 905 ret = snp_prep_cmd_buf(cmd, cmd_buf, desc_list); 906 if (ret) { 907 dev_err(sev->dev, 908 "SEV: failed to prepare buffer for legacy command 0x%x. Error: %d\n", 909 cmd, ret); 910 return ret; 911 } 912 } else { 913 cmd_buf = sev->cmd_buf; 914 } 915 916 /* Get the physical address of the command buffer */ 917 phys_lsb = data ? lower_32_bits(__psp_pa(cmd_buf)) : 0; 918 phys_msb = data ? upper_32_bits(__psp_pa(cmd_buf)) : 0; 919 920 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n", 921 cmd, phys_msb, phys_lsb, psp_timeout); 922 923 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data, 924 buf_len, false); 925 926 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 927 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 928 929 sev->int_rcvd = 0; 930 931 reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd); 932 933 /* 934 * If invoked during panic handling, local interrupts are disabled so 935 * the PSP command completion interrupt can't be used. 936 * sev_wait_cmd_ioc() already checks for interrupts disabled and 937 * polls for PSP command completion. Ensure we do not request an 938 * interrupt from the PSP if irqs disabled. 939 */ 940 if (!irqs_disabled()) 941 reg |= SEV_CMDRESP_IOC; 942 943 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg); 944 945 /* wait for command completion */ 946 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout); 947 if (ret) { 948 if (psp_ret) 949 *psp_ret = 0; 950 951 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd); 952 psp_dead = true; 953 954 return ret; 955 } 956 957 psp_timeout = psp_cmd_timeout; 958 959 if (psp_ret) 960 *psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg); 961 962 if (FIELD_GET(PSP_CMDRESP_STS, reg)) { 963 dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n", 964 cmd, FIELD_GET(PSP_CMDRESP_STS, reg)); 965 966 /* 967 * PSP firmware may report additional error information in the 968 * command buffer registers on error. Print contents of command 969 * buffer registers if they changed. 970 */ 971 cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 972 cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 973 if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) { 974 dev_dbg(sev->dev, "Additional error information reported in cmdbuff:"); 975 dev_dbg(sev->dev, " cmdbuff hi: %#010x\n", cmdbuff_hi); 976 dev_dbg(sev->dev, " cmdbuff lo: %#010x\n", cmdbuff_lo); 977 } 978 ret = -EIO; 979 } else { 980 ret = sev_write_init_ex_file_if_required(cmd); 981 } 982 983 /* 984 * Copy potential output from the PSP back to data. Do this even on 985 * failure in case the caller wants to glean something from the error. 986 */ 987 if (data) { 988 int ret_reclaim; 989 /* 990 * Restore the page state after the command completes. 991 */ 992 ret_reclaim = snp_reclaim_cmd_buf(cmd, cmd_buf); 993 if (ret_reclaim) { 994 dev_err(sev->dev, 995 "SEV: failed to reclaim buffer for legacy command %#x. Error: %d\n", 996 cmd, ret_reclaim); 997 return ret_reclaim; 998 } 999 1000 memcpy(data, cmd_buf, buf_len); 1001 1002 if (sev->cmd_buf_backup_active) 1003 sev->cmd_buf_backup_active = false; 1004 else 1005 sev->cmd_buf_active = false; 1006 1007 if (snp_unmap_cmd_buf_desc_list(desc_list)) 1008 return -EFAULT; 1009 } 1010 1011 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, 1012 buf_len, false); 1013 1014 return ret; 1015 } 1016 1017 int sev_do_cmd(int cmd, void *data, int *psp_ret) 1018 { 1019 int rc; 1020 1021 mutex_lock(&sev_cmd_mutex); 1022 rc = __sev_do_cmd_locked(cmd, data, psp_ret); 1023 mutex_unlock(&sev_cmd_mutex); 1024 1025 return rc; 1026 } 1027 EXPORT_SYMBOL_GPL(sev_do_cmd); 1028 1029 static int __sev_init_locked(int *error) 1030 { 1031 struct sev_data_init data; 1032 1033 memset(&data, 0, sizeof(data)); 1034 if (sev_es_tmr) { 1035 /* 1036 * Do not include the encryption mask on the physical 1037 * address of the TMR (firmware should clear it anyway). 1038 */ 1039 data.tmr_address = __pa(sev_es_tmr); 1040 1041 data.flags |= SEV_INIT_FLAGS_SEV_ES; 1042 data.tmr_len = sev_es_tmr_size; 1043 } 1044 1045 return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); 1046 } 1047 1048 static int __sev_init_ex_locked(int *error) 1049 { 1050 struct sev_data_init_ex data; 1051 1052 memset(&data, 0, sizeof(data)); 1053 data.length = sizeof(data); 1054 data.nv_address = __psp_pa(sev_init_ex_buffer); 1055 data.nv_len = NV_LENGTH; 1056 1057 if (sev_es_tmr) { 1058 /* 1059 * Do not include the encryption mask on the physical 1060 * address of the TMR (firmware should clear it anyway). 1061 */ 1062 data.tmr_address = __pa(sev_es_tmr); 1063 1064 data.flags |= SEV_INIT_FLAGS_SEV_ES; 1065 data.tmr_len = sev_es_tmr_size; 1066 } 1067 1068 return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error); 1069 } 1070 1071 static inline int __sev_do_init_locked(int *psp_ret) 1072 { 1073 if (sev_init_ex_buffer) 1074 return __sev_init_ex_locked(psp_ret); 1075 else 1076 return __sev_init_locked(psp_ret); 1077 } 1078 1079 /* Hypervisor Fixed pages API interface */ 1080 static void snp_hv_fixed_pages_state_update(struct sev_device *sev, 1081 enum snp_hv_fixed_pages_state page_state) 1082 { 1083 struct snp_hv_fixed_pages_entry *entry; 1084 1085 /* List is protected by sev_cmd_mutex */ 1086 lockdep_assert_held(&sev_cmd_mutex); 1087 1088 if (list_empty(&snp_hv_fixed_pages)) 1089 return; 1090 1091 list_for_each_entry(entry, &snp_hv_fixed_pages, list) 1092 entry->page_state = page_state; 1093 } 1094 1095 /* 1096 * Allocate HV_FIXED pages in 2MB aligned sizes to ensure the whole 1097 * 2MB pages are marked as HV_FIXED. 1098 */ 1099 struct page *snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages) 1100 { 1101 struct psp_device *psp_master = psp_get_master_device(); 1102 struct snp_hv_fixed_pages_entry *entry; 1103 unsigned int order; 1104 struct page *page; 1105 1106 if (!psp_master) 1107 return NULL; 1108 1109 order = get_order(PMD_SIZE * num_2mb_pages); 1110 1111 /* 1112 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list 1113 * also needs to be protected using the same mutex. 1114 */ 1115 guard(mutex)(&sev_cmd_mutex); 1116 1117 /* 1118 * This API uses SNP_INIT_EX to transition allocated pages to HV_Fixed 1119 * page state, fail if SNP is already initialized. 1120 */ 1121 if (psp_master->sev_data && 1122 ((struct sev_device *)psp_master->sev_data)->snp_initialized) 1123 return NULL; 1124 1125 /* Re-use freed pages that match the request */ 1126 list_for_each_entry(entry, &snp_hv_fixed_pages, list) { 1127 /* Hypervisor fixed page allocator implements exact fit policy */ 1128 if (entry->order == order && entry->free) { 1129 entry->free = false; 1130 memset(page_address(entry->page), 0, 1131 (1 << entry->order) * PAGE_SIZE); 1132 return entry->page; 1133 } 1134 } 1135 1136 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order); 1137 if (!page) 1138 return NULL; 1139 1140 entry = kzalloc_obj(*entry); 1141 if (!entry) { 1142 __free_pages(page, order); 1143 return NULL; 1144 } 1145 1146 entry->page = page; 1147 entry->order = order; 1148 list_add_tail(&entry->list, &snp_hv_fixed_pages); 1149 1150 return page; 1151 } 1152 1153 void snp_free_hv_fixed_pages(struct page *page) 1154 { 1155 struct psp_device *psp_master = psp_get_master_device(); 1156 struct snp_hv_fixed_pages_entry *entry, *nentry; 1157 1158 if (!psp_master) 1159 return; 1160 1161 /* 1162 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list 1163 * also needs to be protected using the same mutex. 1164 */ 1165 guard(mutex)(&sev_cmd_mutex); 1166 1167 list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) { 1168 if (entry->page != page) 1169 continue; 1170 1171 /* 1172 * HV_FIXED page state cannot be changed until reboot 1173 * and they cannot be used by an SNP guest, so they cannot 1174 * be returned back to the page allocator. 1175 * Mark the pages as free internally to allow possible re-use. 1176 */ 1177 if (entry->page_state == HV_FIXED) { 1178 entry->free = true; 1179 } else { 1180 __free_pages(page, entry->order); 1181 list_del(&entry->list); 1182 kfree(entry); 1183 } 1184 return; 1185 } 1186 } 1187 1188 static void snp_add_hv_fixed_pages(struct sev_device *sev, struct sev_data_range_list *range_list) 1189 { 1190 struct snp_hv_fixed_pages_entry *entry; 1191 struct sev_data_range *range; 1192 int num_elements; 1193 1194 lockdep_assert_held(&sev_cmd_mutex); 1195 1196 if (list_empty(&snp_hv_fixed_pages)) 1197 return; 1198 1199 num_elements = list_count_nodes(&snp_hv_fixed_pages) + 1200 range_list->num_elements; 1201 1202 /* 1203 * Ensure the list of HV_FIXED pages that will be passed to firmware 1204 * do not exceed the page-sized argument buffer. 1205 */ 1206 if (num_elements * sizeof(*range) + sizeof(*range_list) > PAGE_SIZE) { 1207 dev_warn(sev->dev, "Additional HV_Fixed pages cannot be accommodated, omitting\n"); 1208 return; 1209 } 1210 1211 range = &range_list->ranges[range_list->num_elements]; 1212 list_for_each_entry(entry, &snp_hv_fixed_pages, list) { 1213 range->base = page_to_pfn(entry->page) << PAGE_SHIFT; 1214 range->page_count = 1 << entry->order; 1215 range++; 1216 } 1217 range_list->num_elements = num_elements; 1218 } 1219 1220 static void snp_leak_hv_fixed_pages(void) 1221 { 1222 struct snp_hv_fixed_pages_entry *entry; 1223 1224 /* List is protected by sev_cmd_mutex */ 1225 lockdep_assert_held(&sev_cmd_mutex); 1226 1227 if (list_empty(&snp_hv_fixed_pages)) 1228 return; 1229 1230 list_for_each_entry(entry, &snp_hv_fixed_pages, list) 1231 if (entry->page_state == HV_FIXED) 1232 __snp_leak_pages(page_to_pfn(entry->page), 1233 1 << entry->order, false); 1234 } 1235 1236 bool sev_is_snp_ciphertext_hiding_supported(void) 1237 { 1238 struct psp_device *psp = psp_master; 1239 struct sev_device *sev; 1240 1241 if (!psp || !psp->sev_data) 1242 return false; 1243 1244 sev = psp->sev_data; 1245 1246 /* 1247 * Feature information indicates if CipherTextHiding feature is 1248 * supported by the SEV firmware and additionally platform status 1249 * indicates if CipherTextHiding feature is enabled in the 1250 * Platform BIOS. 1251 */ 1252 return ((sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) && 1253 sev->snp_plat_status.ciphertext_hiding_cap); 1254 } 1255 EXPORT_SYMBOL_GPL(sev_is_snp_ciphertext_hiding_supported); 1256 1257 static int snp_get_platform_data(struct sev_device *sev, int *error) 1258 { 1259 struct sev_data_snp_feature_info snp_feat_info; 1260 struct snp_feature_info *feat_info; 1261 struct sev_data_snp_addr buf; 1262 struct page *page; 1263 int rc; 1264 1265 /* 1266 * This function is expected to be called before SNP is 1267 * initialized. 1268 */ 1269 if (sev->snp_initialized) 1270 return -EINVAL; 1271 1272 buf.address = __psp_pa(&sev->snp_plat_status); 1273 rc = sev_do_cmd(SEV_CMD_SNP_PLATFORM_STATUS, &buf, error); 1274 if (rc) { 1275 dev_err(sev->dev, "SNP PLATFORM_STATUS command failed, ret = %d, error = %#x\n", 1276 rc, *error); 1277 return rc; 1278 } 1279 1280 sev->api_major = sev->snp_plat_status.api_major; 1281 sev->api_minor = sev->snp_plat_status.api_minor; 1282 sev->build = sev->snp_plat_status.build_id; 1283 1284 /* 1285 * Do feature discovery of the currently loaded firmware, 1286 * and cache feature information from CPUID 0x8000_0024, 1287 * sub-function 0. 1288 */ 1289 if (!sev->snp_plat_status.feature_info) 1290 return 0; 1291 1292 /* 1293 * Use dynamically allocated structure for the SNP_FEATURE_INFO 1294 * command to ensure structure is 8-byte aligned, and does not 1295 * cross a page boundary. 1296 */ 1297 page = alloc_page(GFP_KERNEL); 1298 if (!page) 1299 return -ENOMEM; 1300 1301 feat_info = page_address(page); 1302 snp_feat_info.length = sizeof(snp_feat_info); 1303 snp_feat_info.ecx_in = 0; 1304 snp_feat_info.feature_info_paddr = __psp_pa(feat_info); 1305 1306 rc = sev_do_cmd(SEV_CMD_SNP_FEATURE_INFO, &snp_feat_info, error); 1307 if (!rc) 1308 sev->snp_feat_info_0 = *feat_info; 1309 else 1310 dev_err(sev->dev, "SNP FEATURE_INFO command failed, ret = %d, error = %#x\n", 1311 rc, *error); 1312 1313 __free_page(page); 1314 1315 return rc; 1316 } 1317 1318 static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg) 1319 { 1320 struct sev_data_range_list *range_list = arg; 1321 struct sev_data_range *range = &range_list->ranges[range_list->num_elements]; 1322 size_t size; 1323 1324 /* 1325 * Ensure the list of HV_FIXED pages that will be passed to firmware 1326 * do not exceed the page-sized argument buffer. 1327 */ 1328 if ((range_list->num_elements * sizeof(struct sev_data_range) + 1329 sizeof(struct sev_data_range_list)) > PAGE_SIZE) 1330 return -E2BIG; 1331 1332 switch (rs->desc) { 1333 case E820_TYPE_RESERVED: 1334 case E820_TYPE_PMEM: 1335 case E820_TYPE_ACPI: 1336 range->base = rs->start & PAGE_MASK; 1337 size = PAGE_ALIGN((rs->end + 1) - rs->start); 1338 range->page_count = size >> PAGE_SHIFT; 1339 range_list->num_elements++; 1340 break; 1341 default: 1342 break; 1343 } 1344 1345 return 0; 1346 } 1347 1348 static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid) 1349 { 1350 struct sev_data_range_list *snp_range_list __free(kfree) = NULL; 1351 struct psp_device *psp = psp_master; 1352 struct sev_data_snp_init_ex data; 1353 struct sev_device *sev; 1354 void *arg = &data; 1355 int cmd, rc = 0; 1356 1357 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) 1358 return -ENODEV; 1359 1360 sev = psp->sev_data; 1361 1362 if (sev->snp_initialized) 1363 return 0; 1364 1365 if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) { 1366 dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n", 1367 SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR); 1368 return -EOPNOTSUPP; 1369 } 1370 1371 snp_prepare(); 1372 1373 /* 1374 * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list 1375 * of system physical address ranges to convert into HV-fixed page 1376 * states during the RMP initialization. For instance, the memory that 1377 * UEFI reserves should be included in the that list. This allows system 1378 * components that occasionally write to memory (e.g. logging to UEFI 1379 * reserved regions) to not fail due to RMP initialization and SNP 1380 * enablement. 1381 * 1382 */ 1383 if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) { 1384 bool tio_supp = !!(sev->snp_feat_info_0.ebx & SNP_SEV_TIO_SUPPORTED); 1385 1386 /* 1387 * Firmware checks that the pages containing the ranges enumerated 1388 * in the RANGES structure are either in the default page state or in the 1389 * firmware page state. 1390 */ 1391 snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL); 1392 if (!snp_range_list) { 1393 dev_err(sev->dev, 1394 "SEV: SNP_INIT_EX range list memory allocation failed\n"); 1395 return -ENOMEM; 1396 } 1397 1398 /* 1399 * Retrieve all reserved memory regions from the e820 memory map 1400 * to be setup as HV-fixed pages. 1401 */ 1402 rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0, 1403 snp_range_list, snp_filter_reserved_mem_regions); 1404 if (rc) { 1405 dev_err(sev->dev, 1406 "SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc); 1407 return rc; 1408 } 1409 1410 /* 1411 * Add HV_Fixed pages from other PSP sub-devices, such as SFS to the 1412 * HV_Fixed page list. 1413 */ 1414 snp_add_hv_fixed_pages(sev, snp_range_list); 1415 1416 memset(&data, 0, sizeof(data)); 1417 1418 if (max_snp_asid) { 1419 data.ciphertext_hiding_en = 1; 1420 data.max_snp_asid = max_snp_asid; 1421 } 1422 1423 data.init_rmp = 1; 1424 data.list_paddr_en = 1; 1425 data.list_paddr = __psp_pa(snp_range_list); 1426 1427 data.tio_en = tio_supp && sev_tio_enabled && amd_iommu_sev_tio_supported(); 1428 1429 /* 1430 * When psp_init_on_probe is disabled, the userspace calling 1431 * SEV ioctl can inadvertently shut down SNP and SEV-TIO causing 1432 * unexpected state loss. 1433 */ 1434 if (data.tio_en && !psp_init_on_probe) 1435 dev_warn(sev->dev, "SEV-TIO as incompatible with psp_init_on_probe=0\n"); 1436 1437 cmd = SEV_CMD_SNP_INIT_EX; 1438 } else { 1439 cmd = SEV_CMD_SNP_INIT; 1440 arg = NULL; 1441 } 1442 1443 /* 1444 * The following sequence must be issued before launching the first SNP 1445 * guest to ensure all dirty cache lines are flushed, including from 1446 * updates to the RMP table itself via the RMPUPDATE instruction: 1447 * 1448 * - WBINVD on all running CPUs 1449 * - SEV_CMD_SNP_INIT[_EX] firmware command 1450 * - WBINVD on all running CPUs 1451 * - SEV_CMD_SNP_DF_FLUSH firmware command 1452 */ 1453 wbinvd_on_all_cpus(); 1454 1455 rc = __sev_do_cmd_locked(cmd, arg, error); 1456 if (rc) { 1457 dev_err(sev->dev, "SEV-SNP: %s failed rc %d, error %#x\n", 1458 cmd == SEV_CMD_SNP_INIT_EX ? "SNP_INIT_EX" : "SNP_INIT", 1459 rc, *error); 1460 return rc; 1461 } 1462 1463 /* Prepare for first SNP guest launch after INIT. */ 1464 wbinvd_on_all_cpus(); 1465 rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error); 1466 if (rc) { 1467 dev_err(sev->dev, "SEV-SNP: SNP_DF_FLUSH failed rc %d, error %#x\n", 1468 rc, *error); 1469 return rc; 1470 } 1471 1472 snp_hv_fixed_pages_state_update(sev, HV_FIXED); 1473 sev->snp_initialized = true; 1474 dev_dbg(sev->dev, "SEV-SNP firmware initialized, SEV-TIO is %s\n", 1475 data.tio_en ? "enabled" : "disabled"); 1476 1477 dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major, 1478 sev->api_minor, sev->build); 1479 1480 atomic_notifier_chain_register(&panic_notifier_list, 1481 &snp_panic_notifier); 1482 1483 if (data.tio_en) { 1484 /* 1485 * This executes with the sev_cmd_mutex held so down the stack 1486 * snp_reclaim_pages(locked=false) might be needed (which is extremely 1487 * unlikely) but will cause a deadlock. 1488 * Instead of exporting __snp_alloc_firmware_pages(), allocate a page 1489 * for this one call here. 1490 */ 1491 void *tio_status = page_address(__snp_alloc_firmware_pages( 1492 GFP_KERNEL_ACCOUNT | __GFP_ZERO, 0, true)); 1493 1494 if (tio_status) { 1495 sev_tsm_init_locked(sev, tio_status); 1496 __snp_free_firmware_pages(virt_to_page(tio_status), 0, true); 1497 } 1498 } 1499 1500 sev_es_tmr_size = SNP_TMR_SIZE; 1501 1502 return 0; 1503 } 1504 1505 static void __sev_platform_init_handle_tmr(struct sev_device *sev) 1506 { 1507 if (sev_es_tmr) 1508 return; 1509 1510 /* Obtain the TMR memory area for SEV-ES use */ 1511 sev_es_tmr = sev_fw_alloc(sev_es_tmr_size); 1512 if (sev_es_tmr) { 1513 /* Must flush the cache before giving it to the firmware */ 1514 if (!sev->snp_initialized) 1515 clflush_cache_range(sev_es_tmr, sev_es_tmr_size); 1516 } else { 1517 dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n"); 1518 } 1519 } 1520 1521 /* 1522 * If an init_ex_path is provided allocate a buffer for the file and 1523 * read in the contents. Additionally, if SNP is initialized, convert 1524 * the buffer pages to firmware pages. 1525 */ 1526 static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev) 1527 { 1528 struct page *page; 1529 int rc; 1530 1531 if (!init_ex_path) 1532 return 0; 1533 1534 if (sev_init_ex_buffer) 1535 return 0; 1536 1537 page = alloc_pages(GFP_KERNEL, get_order(NV_LENGTH)); 1538 if (!page) { 1539 dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n"); 1540 return -ENOMEM; 1541 } 1542 1543 sev_init_ex_buffer = page_address(page); 1544 1545 rc = sev_read_init_ex_file(); 1546 if (rc) 1547 return rc; 1548 1549 /* If SEV-SNP is initialized, transition to firmware page. */ 1550 if (sev->snp_initialized) { 1551 unsigned long npages; 1552 1553 npages = 1UL << get_order(NV_LENGTH); 1554 if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, false)) { 1555 dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n"); 1556 return -ENOMEM; 1557 } 1558 } 1559 1560 return 0; 1561 } 1562 1563 static int __sev_platform_init_locked(int *error) 1564 { 1565 int rc, psp_ret, dfflush_error; 1566 struct sev_device *sev; 1567 1568 psp_ret = dfflush_error = SEV_RET_NO_FW_CALL; 1569 1570 if (!psp_master || !psp_master->sev_data) 1571 return -ENODEV; 1572 1573 sev = psp_master->sev_data; 1574 1575 if (sev->sev_plat_status.state == SEV_STATE_INIT) 1576 return 0; 1577 1578 __sev_platform_init_handle_tmr(sev); 1579 1580 rc = __sev_platform_init_handle_init_ex_path(sev); 1581 if (rc) 1582 return rc; 1583 1584 rc = __sev_do_init_locked(&psp_ret); 1585 if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) { 1586 /* 1587 * Initialization command returned an integrity check failure 1588 * status code, meaning that firmware load and validation of SEV 1589 * related persistent data has failed. Retrying the 1590 * initialization function should succeed by replacing the state 1591 * with a reset state. 1592 */ 1593 dev_err(sev->dev, 1594 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state."); 1595 rc = __sev_do_init_locked(&psp_ret); 1596 } 1597 1598 if (error) 1599 *error = psp_ret; 1600 1601 if (rc) { 1602 dev_err(sev->dev, "SEV: %s failed %#x, rc %d\n", 1603 sev_init_ex_buffer ? "INIT_EX" : "INIT", psp_ret, rc); 1604 return rc; 1605 } 1606 1607 sev->sev_plat_status.state = SEV_STATE_INIT; 1608 1609 /* Prepare for first SEV guest launch after INIT */ 1610 wbinvd_on_all_cpus(); 1611 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, &dfflush_error); 1612 if (rc) { 1613 dev_err(sev->dev, "SEV: DF_FLUSH failed %#x, rc %d\n", 1614 dfflush_error, rc); 1615 return rc; 1616 } 1617 1618 dev_dbg(sev->dev, "SEV firmware initialized\n"); 1619 1620 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major, 1621 sev->api_minor, sev->build); 1622 1623 return 0; 1624 } 1625 1626 static int _sev_platform_init_locked(struct sev_platform_init_args *args) 1627 { 1628 struct sev_device *sev; 1629 int rc; 1630 1631 if (!psp_master || !psp_master->sev_data) 1632 return -ENODEV; 1633 1634 /* 1635 * Skip SNP/SEV initialization under a kdump kernel as SEV/SNP 1636 * may already be initialized in the previous kernel. Since no 1637 * SNP/SEV guests are run under a kdump kernel, there is no 1638 * need to initialize SNP or SEV during kdump boot. 1639 */ 1640 if (is_kdump_kernel()) 1641 return 0; 1642 1643 sev = psp_master->sev_data; 1644 1645 if (sev->sev_plat_status.state == SEV_STATE_INIT) 1646 return 0; 1647 1648 rc = __sev_snp_init_locked(&args->error, args->max_snp_asid); 1649 if (rc && rc != -ENODEV) 1650 return rc; 1651 1652 /* Defer legacy SEV/SEV-ES support if allowed by caller/module. */ 1653 if (args->probe && !psp_init_on_probe) 1654 return 0; 1655 1656 return __sev_platform_init_locked(&args->error); 1657 } 1658 1659 int sev_platform_init(struct sev_platform_init_args *args) 1660 { 1661 int rc; 1662 1663 mutex_lock(&sev_cmd_mutex); 1664 rc = _sev_platform_init_locked(args); 1665 mutex_unlock(&sev_cmd_mutex); 1666 1667 return rc; 1668 } 1669 EXPORT_SYMBOL_GPL(sev_platform_init); 1670 1671 static int __sev_platform_shutdown_locked(int *error) 1672 { 1673 struct psp_device *psp = psp_master; 1674 struct sev_device *sev; 1675 int ret; 1676 1677 if (!psp || !psp->sev_data) 1678 return 0; 1679 1680 sev = psp->sev_data; 1681 1682 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) 1683 return 0; 1684 1685 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error); 1686 if (ret) { 1687 dev_err(sev->dev, "SEV: failed to SHUTDOWN error %#x, rc %d\n", 1688 *error, ret); 1689 return ret; 1690 } 1691 1692 sev->sev_plat_status.state = SEV_STATE_UNINIT; 1693 dev_dbg(sev->dev, "SEV firmware shutdown\n"); 1694 1695 return ret; 1696 } 1697 1698 static int sev_get_platform_state(int *state, int *error) 1699 { 1700 struct sev_user_data_status data; 1701 int rc; 1702 1703 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error); 1704 if (rc) 1705 return rc; 1706 1707 *state = data.state; 1708 return rc; 1709 } 1710 1711 static int sev_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required) 1712 { 1713 struct sev_platform_init_args init_args = {0}; 1714 int rc; 1715 1716 rc = _sev_platform_init_locked(&init_args); 1717 if (rc) { 1718 argp->error = SEV_RET_INVALID_PLATFORM_STATE; 1719 return rc; 1720 } 1721 1722 *shutdown_required = true; 1723 1724 return 0; 1725 } 1726 1727 static int snp_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required) 1728 { 1729 int error, rc; 1730 1731 rc = __sev_snp_init_locked(&error, 0); 1732 if (rc) { 1733 argp->error = SEV_RET_INVALID_PLATFORM_STATE; 1734 return rc; 1735 } 1736 1737 *shutdown_required = true; 1738 1739 return 0; 1740 } 1741 1742 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable) 1743 { 1744 int state, rc; 1745 1746 if (!writable) 1747 return -EPERM; 1748 1749 /* 1750 * The SEV spec requires that FACTORY_RESET must be issued in 1751 * UNINIT state. Before we go further lets check if any guest is 1752 * active. 1753 * 1754 * If FW is in WORKING state then deny the request otherwise issue 1755 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET. 1756 * 1757 */ 1758 rc = sev_get_platform_state(&state, &argp->error); 1759 if (rc) 1760 return rc; 1761 1762 if (state == SEV_STATE_WORKING) 1763 return -EBUSY; 1764 1765 if (state == SEV_STATE_INIT) { 1766 rc = __sev_platform_shutdown_locked(&argp->error); 1767 if (rc) 1768 return rc; 1769 } 1770 1771 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error); 1772 } 1773 1774 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp) 1775 { 1776 struct sev_user_data_status data; 1777 int ret; 1778 1779 memset(&data, 0, sizeof(data)); 1780 1781 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error); 1782 if (ret) 1783 return ret; 1784 1785 if (copy_to_user((void __user *)argp->data, &data, sizeof(data))) 1786 ret = -EFAULT; 1787 1788 return ret; 1789 } 1790 1791 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable) 1792 { 1793 struct sev_device *sev = psp_master->sev_data; 1794 bool shutdown_required = false; 1795 int rc; 1796 1797 if (!writable) 1798 return -EPERM; 1799 1800 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) { 1801 rc = sev_move_to_init_state(argp, &shutdown_required); 1802 if (rc) 1803 return rc; 1804 } 1805 1806 rc = __sev_do_cmd_locked(cmd, NULL, &argp->error); 1807 1808 if (shutdown_required) 1809 __sev_firmware_shutdown(sev, false); 1810 1811 return rc; 1812 } 1813 1814 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable) 1815 { 1816 struct sev_device *sev = psp_master->sev_data; 1817 struct sev_user_data_pek_csr input; 1818 bool shutdown_required = false; 1819 struct sev_data_pek_csr data; 1820 void __user *input_address; 1821 void *blob = NULL; 1822 int ret; 1823 1824 if (!writable) 1825 return -EPERM; 1826 1827 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 1828 return -EFAULT; 1829 1830 memset(&data, 0, sizeof(data)); 1831 1832 /* userspace wants to query CSR length */ 1833 if (!input.address || !input.length) 1834 goto cmd; 1835 1836 /* allocate a physically contiguous buffer to store the CSR blob */ 1837 input_address = (void __user *)input.address; 1838 if (input.length > SEV_FW_BLOB_MAX_SIZE) 1839 return -EFAULT; 1840 1841 blob = kzalloc(input.length, GFP_KERNEL); 1842 if (!blob) 1843 return -ENOMEM; 1844 1845 data.address = __psp_pa(blob); 1846 data.len = input.length; 1847 1848 cmd: 1849 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) { 1850 ret = sev_move_to_init_state(argp, &shutdown_required); 1851 if (ret) 1852 goto e_free_blob; 1853 } 1854 1855 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error); 1856 1857 /* If we query the CSR length, FW responded with expected data. */ 1858 input.length = data.len; 1859 1860 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 1861 ret = -EFAULT; 1862 goto e_free_blob; 1863 } 1864 1865 if (blob) { 1866 if (copy_to_user(input_address, blob, input.length)) 1867 ret = -EFAULT; 1868 } 1869 1870 e_free_blob: 1871 if (shutdown_required) 1872 __sev_firmware_shutdown(sev, false); 1873 1874 kfree(blob); 1875 return ret; 1876 } 1877 1878 void *psp_copy_user_blob(u64 uaddr, u32 len) 1879 { 1880 if (!uaddr || !len) 1881 return ERR_PTR(-EINVAL); 1882 1883 /* verify that blob length does not exceed our limit */ 1884 if (len > SEV_FW_BLOB_MAX_SIZE) 1885 return ERR_PTR(-EINVAL); 1886 1887 return memdup_user((void __user *)uaddr, len); 1888 } 1889 EXPORT_SYMBOL_GPL(psp_copy_user_blob); 1890 1891 static int sev_get_api_version(void) 1892 { 1893 struct sev_device *sev = psp_master->sev_data; 1894 struct sev_user_data_status status; 1895 int error = 0, ret; 1896 1897 /* 1898 * Cache SNP platform status and SNP feature information 1899 * if SNP is available. 1900 */ 1901 if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) { 1902 ret = snp_get_platform_data(sev, &error); 1903 if (ret) 1904 return 1; 1905 } 1906 1907 ret = sev_platform_status(&status, &error); 1908 if (ret) { 1909 dev_err(sev->dev, 1910 "SEV: failed to get status. Error: %#x\n", error); 1911 return 1; 1912 } 1913 1914 /* Cache SEV platform status */ 1915 sev->sev_plat_status = status; 1916 1917 sev->api_major = status.api_major; 1918 sev->api_minor = status.api_minor; 1919 sev->build = status.build; 1920 1921 return 0; 1922 } 1923 1924 static int sev_get_firmware(struct device *dev, 1925 const struct firmware **firmware) 1926 { 1927 char fw_name_specific[SEV_FW_NAME_SIZE]; 1928 char fw_name_subset[SEV_FW_NAME_SIZE]; 1929 1930 snprintf(fw_name_specific, sizeof(fw_name_specific), 1931 "amd/amd_sev_fam%.2xh_model%.2xh.sbin", 1932 boot_cpu_data.x86, boot_cpu_data.x86_model); 1933 1934 snprintf(fw_name_subset, sizeof(fw_name_subset), 1935 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin", 1936 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4); 1937 1938 /* Check for SEV FW for a particular model. 1939 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h 1940 * 1941 * or 1942 * 1943 * Check for SEV FW common to a subset of models. 1944 * Ex. amd_sev_fam17h_model0xh.sbin for 1945 * Family 17h Model 00h -- Family 17h Model 0Fh 1946 * 1947 * or 1948 * 1949 * Fall-back to using generic name: sev.fw 1950 */ 1951 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) || 1952 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) || 1953 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0)) 1954 return 0; 1955 1956 return -ENOENT; 1957 } 1958 1959 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */ 1960 static int sev_update_firmware(struct device *dev) 1961 { 1962 struct sev_data_download_firmware *data; 1963 const struct firmware *firmware; 1964 int ret, error, order; 1965 struct page *p; 1966 u64 data_size; 1967 1968 if (!sev_version_greater_or_equal(0, 15)) { 1969 dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n"); 1970 return -1; 1971 } 1972 1973 if (sev_get_firmware(dev, &firmware) == -ENOENT) { 1974 dev_dbg(dev, "No SEV firmware file present\n"); 1975 return -1; 1976 } 1977 1978 /* 1979 * SEV FW expects the physical address given to it to be 32 1980 * byte aligned. Memory allocated has structure placed at the 1981 * beginning followed by the firmware being passed to the SEV 1982 * FW. Allocate enough memory for data structure + alignment 1983 * padding + SEV FW. 1984 */ 1985 data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32); 1986 1987 order = get_order(firmware->size + data_size); 1988 p = alloc_pages(GFP_KERNEL, order); 1989 if (!p) { 1990 ret = -1; 1991 goto fw_err; 1992 } 1993 1994 /* 1995 * Copy firmware data to a kernel allocated contiguous 1996 * memory region. 1997 */ 1998 data = page_address(p); 1999 memcpy(page_address(p) + data_size, firmware->data, firmware->size); 2000 2001 data->address = __psp_pa(page_address(p) + data_size); 2002 data->len = firmware->size; 2003 2004 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); 2005 2006 /* 2007 * A quirk for fixing the committed TCB version, when upgrading from 2008 * earlier firmware version than 1.50. 2009 */ 2010 if (!ret && !sev_version_greater_or_equal(1, 50)) 2011 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); 2012 2013 if (ret) 2014 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error); 2015 2016 __free_pages(p, order); 2017 2018 fw_err: 2019 release_firmware(firmware); 2020 2021 return ret; 2022 } 2023 2024 static int __sev_snp_shutdown_locked(int *error, bool panic) 2025 { 2026 struct psp_device *psp = psp_master; 2027 struct sev_device *sev; 2028 struct sev_data_snp_shutdown_ex data; 2029 int ret; 2030 2031 if (!psp || !psp->sev_data) 2032 return 0; 2033 2034 sev = psp->sev_data; 2035 2036 if (!sev->snp_initialized) 2037 return 0; 2038 2039 memset(&data, 0, sizeof(data)); 2040 data.len = sizeof(data); 2041 data.iommu_snp_shutdown = 1; 2042 2043 /* 2044 * If invoked during panic handling, local interrupts are disabled 2045 * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called. 2046 * In that case, a wbinvd() is done on remote CPUs via the NMI 2047 * callback, so only a local wbinvd() is needed here. 2048 */ 2049 if (!panic) 2050 wbinvd_on_all_cpus(); 2051 else 2052 wbinvd(); 2053 2054 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error); 2055 /* SHUTDOWN may require DF_FLUSH */ 2056 if (*error == SEV_RET_DFFLUSH_REQUIRED) { 2057 int dfflush_error = SEV_RET_NO_FW_CALL; 2058 2059 ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, &dfflush_error); 2060 if (ret) { 2061 dev_err(sev->dev, "SEV-SNP DF_FLUSH failed, ret = %d, error = %#x\n", 2062 ret, dfflush_error); 2063 return ret; 2064 } 2065 /* reissue the shutdown command */ 2066 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, 2067 error); 2068 } 2069 if (ret) { 2070 dev_err(sev->dev, "SEV-SNP firmware shutdown failed, rc %d, error %#x\n", 2071 ret, *error); 2072 return ret; 2073 } 2074 2075 /* 2076 * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP 2077 * enforcement by the IOMMU and also transitions all pages 2078 * associated with the IOMMU to the Reclaim state. 2079 * Firmware was transitioning the IOMMU pages to Hypervisor state 2080 * before version 1.53. But, accounting for the number of assigned 2081 * 4kB pages in a 2M page was done incorrectly by not transitioning 2082 * to the Reclaim state. This resulted in RMP #PF when later accessing 2083 * the 2M page containing those pages during kexec boot. Hence, the 2084 * firmware now transitions these pages to Reclaim state and hypervisor 2085 * needs to transition these pages to shared state. SNP Firmware 2086 * version 1.53 and above are needed for kexec boot. 2087 */ 2088 ret = amd_iommu_snp_disable(); 2089 if (ret) { 2090 dev_err(sev->dev, "SNP IOMMU shutdown failed\n"); 2091 return ret; 2092 } 2093 2094 snp_leak_hv_fixed_pages(); 2095 sev->snp_initialized = false; 2096 dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n"); 2097 2098 /* 2099 * __sev_snp_shutdown_locked() deadlocks when it tries to unregister 2100 * itself during panic as the panic notifier is called with RCU read 2101 * lock held and notifier unregistration does RCU synchronization. 2102 */ 2103 if (!panic) 2104 atomic_notifier_chain_unregister(&panic_notifier_list, 2105 &snp_panic_notifier); 2106 2107 /* Reset TMR size back to default */ 2108 sev_es_tmr_size = SEV_TMR_SIZE; 2109 2110 return ret; 2111 } 2112 2113 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable) 2114 { 2115 struct sev_device *sev = psp_master->sev_data; 2116 struct sev_user_data_pek_cert_import input; 2117 struct sev_data_pek_cert_import data; 2118 bool shutdown_required = false; 2119 void *pek_blob, *oca_blob; 2120 int ret; 2121 2122 if (!writable) 2123 return -EPERM; 2124 2125 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 2126 return -EFAULT; 2127 2128 /* copy PEK certificate blobs from userspace */ 2129 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len); 2130 if (IS_ERR(pek_blob)) 2131 return PTR_ERR(pek_blob); 2132 2133 data.reserved = 0; 2134 data.pek_cert_address = __psp_pa(pek_blob); 2135 data.pek_cert_len = input.pek_cert_len; 2136 2137 /* copy PEK certificate blobs from userspace */ 2138 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len); 2139 if (IS_ERR(oca_blob)) { 2140 ret = PTR_ERR(oca_blob); 2141 goto e_free_pek; 2142 } 2143 2144 data.oca_cert_address = __psp_pa(oca_blob); 2145 data.oca_cert_len = input.oca_cert_len; 2146 2147 /* If platform is not in INIT state then transition it to INIT */ 2148 if (sev->sev_plat_status.state != SEV_STATE_INIT) { 2149 ret = sev_move_to_init_state(argp, &shutdown_required); 2150 if (ret) 2151 goto e_free_oca; 2152 } 2153 2154 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error); 2155 2156 e_free_oca: 2157 if (shutdown_required) 2158 __sev_firmware_shutdown(sev, false); 2159 2160 kfree(oca_blob); 2161 e_free_pek: 2162 kfree(pek_blob); 2163 return ret; 2164 } 2165 2166 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp) 2167 { 2168 struct sev_user_data_get_id2 input; 2169 struct sev_data_get_id data; 2170 void __user *input_address; 2171 void *id_blob = NULL; 2172 int ret; 2173 2174 /* SEV GET_ID is available from SEV API v0.16 and up */ 2175 if (!sev_version_greater_or_equal(0, 16)) 2176 return -ENOTSUPP; 2177 2178 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 2179 return -EFAULT; 2180 2181 input_address = (void __user *)input.address; 2182 2183 if (input.address && input.length) { 2184 /* 2185 * The length of the ID shouldn't be assumed by software since 2186 * it may change in the future. The allocation size is limited 2187 * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator. 2188 * If the allocation fails, simply return ENOMEM rather than 2189 * warning in the kernel log. 2190 */ 2191 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN); 2192 if (!id_blob) 2193 return -ENOMEM; 2194 2195 data.address = __psp_pa(id_blob); 2196 data.len = input.length; 2197 } else { 2198 data.address = 0; 2199 data.len = 0; 2200 } 2201 2202 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error); 2203 2204 /* 2205 * Firmware will return the length of the ID value (either the minimum 2206 * required length or the actual length written), return it to the user. 2207 */ 2208 input.length = data.len; 2209 2210 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 2211 ret = -EFAULT; 2212 goto e_free; 2213 } 2214 2215 if (id_blob) { 2216 if (copy_to_user(input_address, id_blob, data.len)) { 2217 ret = -EFAULT; 2218 goto e_free; 2219 } 2220 } 2221 2222 e_free: 2223 kfree(id_blob); 2224 2225 return ret; 2226 } 2227 2228 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp) 2229 { 2230 struct sev_data_get_id *data; 2231 u64 data_size, user_size; 2232 void *id_blob, *mem; 2233 int ret; 2234 2235 /* SEV GET_ID available from SEV API v0.16 and up */ 2236 if (!sev_version_greater_or_equal(0, 16)) 2237 return -ENOTSUPP; 2238 2239 /* SEV FW expects the buffer it fills with the ID to be 2240 * 8-byte aligned. Memory allocated should be enough to 2241 * hold data structure + alignment padding + memory 2242 * where SEV FW writes the ID. 2243 */ 2244 data_size = ALIGN(sizeof(struct sev_data_get_id), 8); 2245 user_size = sizeof(struct sev_user_data_get_id); 2246 2247 mem = kzalloc(data_size + user_size, GFP_KERNEL); 2248 if (!mem) 2249 return -ENOMEM; 2250 2251 data = mem; 2252 id_blob = mem + data_size; 2253 2254 data->address = __psp_pa(id_blob); 2255 data->len = user_size; 2256 2257 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error); 2258 if (!ret) { 2259 if (copy_to_user((void __user *)argp->data, id_blob, data->len)) 2260 ret = -EFAULT; 2261 } 2262 2263 kfree(mem); 2264 2265 return ret; 2266 } 2267 2268 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable) 2269 { 2270 struct sev_device *sev = psp_master->sev_data; 2271 struct sev_user_data_pdh_cert_export input; 2272 void *pdh_blob = NULL, *cert_blob = NULL; 2273 struct sev_data_pdh_cert_export data; 2274 void __user *input_cert_chain_address; 2275 void __user *input_pdh_cert_address; 2276 bool shutdown_required = false; 2277 int ret; 2278 2279 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 2280 return -EFAULT; 2281 2282 memset(&data, 0, sizeof(data)); 2283 2284 input_pdh_cert_address = (void __user *)input.pdh_cert_address; 2285 input_cert_chain_address = (void __user *)input.cert_chain_address; 2286 2287 /* Userspace wants to query the certificate length. */ 2288 if (!input.pdh_cert_address || 2289 !input.pdh_cert_len || 2290 !input.cert_chain_address) 2291 goto cmd; 2292 2293 /* Allocate a physically contiguous buffer to store the PDH blob. */ 2294 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) 2295 return -EFAULT; 2296 2297 /* Allocate a physically contiguous buffer to store the cert chain blob. */ 2298 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) 2299 return -EFAULT; 2300 2301 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL); 2302 if (!pdh_blob) 2303 return -ENOMEM; 2304 2305 data.pdh_cert_address = __psp_pa(pdh_blob); 2306 data.pdh_cert_len = input.pdh_cert_len; 2307 2308 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL); 2309 if (!cert_blob) { 2310 ret = -ENOMEM; 2311 goto e_free_pdh; 2312 } 2313 2314 data.cert_chain_address = __psp_pa(cert_blob); 2315 data.cert_chain_len = input.cert_chain_len; 2316 2317 cmd: 2318 /* If platform is not in INIT state then transition it to INIT. */ 2319 if (sev->sev_plat_status.state != SEV_STATE_INIT) { 2320 if (!writable) { 2321 ret = -EPERM; 2322 goto e_free_cert; 2323 } 2324 ret = sev_move_to_init_state(argp, &shutdown_required); 2325 if (ret) 2326 goto e_free_cert; 2327 } 2328 2329 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error); 2330 2331 /* If we query the length, FW responded with expected data. */ 2332 input.cert_chain_len = data.cert_chain_len; 2333 input.pdh_cert_len = data.pdh_cert_len; 2334 2335 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 2336 ret = -EFAULT; 2337 goto e_free_cert; 2338 } 2339 2340 if (pdh_blob) { 2341 if (copy_to_user(input_pdh_cert_address, 2342 pdh_blob, input.pdh_cert_len)) { 2343 ret = -EFAULT; 2344 goto e_free_cert; 2345 } 2346 } 2347 2348 if (cert_blob) { 2349 if (copy_to_user(input_cert_chain_address, 2350 cert_blob, input.cert_chain_len)) 2351 ret = -EFAULT; 2352 } 2353 2354 e_free_cert: 2355 if (shutdown_required) 2356 __sev_firmware_shutdown(sev, false); 2357 2358 kfree(cert_blob); 2359 e_free_pdh: 2360 kfree(pdh_blob); 2361 return ret; 2362 } 2363 2364 static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp) 2365 { 2366 struct sev_device *sev = psp_master->sev_data; 2367 struct sev_data_snp_addr buf; 2368 struct page *status_page; 2369 void *data; 2370 int ret; 2371 2372 if (!argp->data) 2373 return -EINVAL; 2374 2375 status_page = alloc_page(GFP_KERNEL_ACCOUNT); 2376 if (!status_page) 2377 return -ENOMEM; 2378 2379 data = page_address(status_page); 2380 2381 /* 2382 * SNP_PLATFORM_STATUS can be executed in any SNP state. But if executed 2383 * when SNP has been initialized, the status page must be firmware-owned. 2384 */ 2385 if (sev->snp_initialized) { 2386 /* 2387 * Firmware expects the status page to be in Firmware state, 2388 * otherwise it will report an error INVALID_PAGE_STATE. 2389 */ 2390 if (rmp_mark_pages_firmware(__pa(data), 1, true)) { 2391 ret = -EFAULT; 2392 goto cleanup; 2393 } 2394 } 2395 2396 buf.address = __psp_pa(data); 2397 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error); 2398 2399 if (sev->snp_initialized) { 2400 /* 2401 * The status page will be in Reclaim state on success, or left 2402 * in Firmware state on failure. Use snp_reclaim_pages() to 2403 * transition either case back to Hypervisor-owned state. 2404 */ 2405 if (snp_reclaim_pages(__pa(data), 1, true)) { 2406 snp_leak_pages(__page_to_pfn(status_page), 1); 2407 return -EFAULT; 2408 } 2409 } 2410 2411 if (ret) 2412 goto cleanup; 2413 2414 if (copy_to_user((void __user *)argp->data, data, 2415 sizeof(struct sev_user_data_snp_status))) 2416 ret = -EFAULT; 2417 2418 cleanup: 2419 __free_pages(status_page, 0); 2420 return ret; 2421 } 2422 2423 static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp) 2424 { 2425 struct sev_device *sev = psp_master->sev_data; 2426 struct sev_data_snp_commit buf; 2427 bool shutdown_required = false; 2428 int ret, error; 2429 2430 if (!sev->snp_initialized) { 2431 ret = snp_move_to_init_state(argp, &shutdown_required); 2432 if (ret) 2433 return ret; 2434 } 2435 2436 buf.len = sizeof(buf); 2437 2438 ret = __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error); 2439 2440 if (shutdown_required) 2441 __sev_snp_shutdown_locked(&error, false); 2442 2443 return ret; 2444 } 2445 2446 static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable) 2447 { 2448 struct sev_device *sev = psp_master->sev_data; 2449 struct sev_user_data_snp_config config; 2450 bool shutdown_required = false; 2451 int ret, error; 2452 2453 if (!argp->data) 2454 return -EINVAL; 2455 2456 if (!writable) 2457 return -EPERM; 2458 2459 if (copy_from_user(&config, (void __user *)argp->data, sizeof(config))) 2460 return -EFAULT; 2461 2462 if (!sev->snp_initialized) { 2463 ret = snp_move_to_init_state(argp, &shutdown_required); 2464 if (ret) 2465 return ret; 2466 } 2467 2468 ret = __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error); 2469 2470 if (shutdown_required) 2471 __sev_snp_shutdown_locked(&error, false); 2472 2473 return ret; 2474 } 2475 2476 static int sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd *argp, bool writable) 2477 { 2478 struct sev_device *sev = psp_master->sev_data; 2479 struct sev_user_data_snp_vlek_load input; 2480 bool shutdown_required = false; 2481 int ret, error; 2482 void *blob; 2483 2484 if (!argp->data) 2485 return -EINVAL; 2486 2487 if (!writable) 2488 return -EPERM; 2489 2490 if (copy_from_user(&input, u64_to_user_ptr(argp->data), sizeof(input))) 2491 return -EFAULT; 2492 2493 if (input.len != sizeof(input) || input.vlek_wrapped_version != 0) 2494 return -EINVAL; 2495 2496 blob = psp_copy_user_blob(input.vlek_wrapped_address, 2497 sizeof(struct sev_user_data_snp_wrapped_vlek_hashstick)); 2498 if (IS_ERR(blob)) 2499 return PTR_ERR(blob); 2500 2501 input.vlek_wrapped_address = __psp_pa(blob); 2502 2503 if (!sev->snp_initialized) { 2504 ret = snp_move_to_init_state(argp, &shutdown_required); 2505 if (ret) 2506 goto cleanup; 2507 } 2508 2509 ret = __sev_do_cmd_locked(SEV_CMD_SNP_VLEK_LOAD, &input, &argp->error); 2510 2511 if (shutdown_required) 2512 __sev_snp_shutdown_locked(&error, false); 2513 2514 cleanup: 2515 kfree(blob); 2516 2517 return ret; 2518 } 2519 2520 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) 2521 { 2522 void __user *argp = (void __user *)arg; 2523 struct sev_issue_cmd input; 2524 int ret = -EFAULT; 2525 bool writable = file->f_mode & FMODE_WRITE; 2526 2527 if (!psp_master || !psp_master->sev_data) 2528 return -ENODEV; 2529 2530 if (ioctl != SEV_ISSUE_CMD) 2531 return -EINVAL; 2532 2533 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd))) 2534 return -EFAULT; 2535 2536 if (input.cmd > SEV_MAX) 2537 return -EINVAL; 2538 2539 mutex_lock(&sev_cmd_mutex); 2540 2541 switch (input.cmd) { 2542 2543 case SEV_FACTORY_RESET: 2544 ret = sev_ioctl_do_reset(&input, writable); 2545 break; 2546 case SEV_PLATFORM_STATUS: 2547 ret = sev_ioctl_do_platform_status(&input); 2548 break; 2549 case SEV_PEK_GEN: 2550 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable); 2551 break; 2552 case SEV_PDH_GEN: 2553 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable); 2554 break; 2555 case SEV_PEK_CSR: 2556 ret = sev_ioctl_do_pek_csr(&input, writable); 2557 break; 2558 case SEV_PEK_CERT_IMPORT: 2559 ret = sev_ioctl_do_pek_import(&input, writable); 2560 break; 2561 case SEV_PDH_CERT_EXPORT: 2562 ret = sev_ioctl_do_pdh_export(&input, writable); 2563 break; 2564 case SEV_GET_ID: 2565 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n"); 2566 ret = sev_ioctl_do_get_id(&input); 2567 break; 2568 case SEV_GET_ID2: 2569 ret = sev_ioctl_do_get_id2(&input); 2570 break; 2571 case SNP_PLATFORM_STATUS: 2572 ret = sev_ioctl_do_snp_platform_status(&input); 2573 break; 2574 case SNP_COMMIT: 2575 ret = sev_ioctl_do_snp_commit(&input); 2576 break; 2577 case SNP_SET_CONFIG: 2578 ret = sev_ioctl_do_snp_set_config(&input, writable); 2579 break; 2580 case SNP_VLEK_LOAD: 2581 ret = sev_ioctl_do_snp_vlek_load(&input, writable); 2582 break; 2583 default: 2584 ret = -EINVAL; 2585 goto out; 2586 } 2587 2588 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd))) 2589 ret = -EFAULT; 2590 out: 2591 mutex_unlock(&sev_cmd_mutex); 2592 2593 return ret; 2594 } 2595 2596 static const struct file_operations sev_fops = { 2597 .owner = THIS_MODULE, 2598 .unlocked_ioctl = sev_ioctl, 2599 }; 2600 2601 int sev_platform_status(struct sev_user_data_status *data, int *error) 2602 { 2603 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error); 2604 } 2605 EXPORT_SYMBOL_GPL(sev_platform_status); 2606 2607 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error) 2608 { 2609 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error); 2610 } 2611 EXPORT_SYMBOL_GPL(sev_guest_deactivate); 2612 2613 int sev_guest_activate(struct sev_data_activate *data, int *error) 2614 { 2615 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error); 2616 } 2617 EXPORT_SYMBOL_GPL(sev_guest_activate); 2618 2619 int sev_guest_decommission(struct sev_data_decommission *data, int *error) 2620 { 2621 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error); 2622 } 2623 EXPORT_SYMBOL_GPL(sev_guest_decommission); 2624 2625 int sev_guest_df_flush(int *error) 2626 { 2627 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error); 2628 } 2629 EXPORT_SYMBOL_GPL(sev_guest_df_flush); 2630 2631 static void sev_exit(struct kref *ref) 2632 { 2633 misc_deregister(&misc_dev->misc); 2634 kfree(misc_dev); 2635 misc_dev = NULL; 2636 } 2637 2638 static int sev_misc_init(struct sev_device *sev) 2639 { 2640 struct device *dev = sev->dev; 2641 int ret; 2642 2643 /* 2644 * SEV feature support can be detected on multiple devices but the SEV 2645 * FW commands must be issued on the master. During probe, we do not 2646 * know the master hence we create /dev/sev on the first device probe. 2647 * sev_do_cmd() finds the right master device to which to issue the 2648 * command to the firmware. 2649 */ 2650 if (!misc_dev) { 2651 struct miscdevice *misc; 2652 2653 misc_dev = kzalloc_obj(*misc_dev); 2654 if (!misc_dev) 2655 return -ENOMEM; 2656 2657 misc = &misc_dev->misc; 2658 misc->minor = MISC_DYNAMIC_MINOR; 2659 misc->name = DEVICE_NAME; 2660 misc->fops = &sev_fops; 2661 2662 ret = misc_register(misc); 2663 if (ret) 2664 return ret; 2665 2666 kref_init(&misc_dev->refcount); 2667 } else { 2668 kref_get(&misc_dev->refcount); 2669 } 2670 2671 init_waitqueue_head(&sev->int_queue); 2672 sev->misc = misc_dev; 2673 dev_dbg(dev, "registered SEV device\n"); 2674 2675 return 0; 2676 } 2677 2678 int sev_dev_init(struct psp_device *psp) 2679 { 2680 struct device *dev = psp->dev; 2681 struct sev_device *sev; 2682 int ret = -ENOMEM; 2683 2684 if (!boot_cpu_has(X86_FEATURE_SEV)) { 2685 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n"); 2686 return 0; 2687 } 2688 2689 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL); 2690 if (!sev) 2691 goto e_err; 2692 2693 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1); 2694 if (!sev->cmd_buf) 2695 goto e_sev; 2696 2697 sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE; 2698 2699 psp->sev_data = sev; 2700 2701 sev->dev = dev; 2702 sev->psp = psp; 2703 2704 sev->io_regs = psp->io_regs; 2705 2706 sev->vdata = (struct sev_vdata *)psp->vdata->sev; 2707 if (!sev->vdata) { 2708 ret = -ENODEV; 2709 dev_err(dev, "sev: missing driver data\n"); 2710 goto e_buf; 2711 } 2712 2713 psp_set_sev_irq_handler(psp, sev_irq_handler, sev); 2714 2715 ret = sev_misc_init(sev); 2716 if (ret) 2717 goto e_irq; 2718 2719 dev_notice(dev, "sev enabled\n"); 2720 2721 return 0; 2722 2723 e_irq: 2724 psp_clear_sev_irq_handler(psp); 2725 e_buf: 2726 devm_free_pages(dev, (unsigned long)sev->cmd_buf); 2727 e_sev: 2728 devm_kfree(dev, sev); 2729 e_err: 2730 psp->sev_data = NULL; 2731 2732 dev_notice(dev, "sev initialization failed\n"); 2733 2734 return ret; 2735 } 2736 2737 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic) 2738 { 2739 int error; 2740 2741 __sev_platform_shutdown_locked(&error); 2742 2743 if (sev_es_tmr) { 2744 /* 2745 * The TMR area was encrypted, flush it from the cache. 2746 * 2747 * If invoked during panic handling, local interrupts are 2748 * disabled and all CPUs are stopped, so wbinvd_on_all_cpus() 2749 * can't be used. In that case, wbinvd() is done on remote CPUs 2750 * via the NMI callback, and done for this CPU later during 2751 * SNP shutdown, so wbinvd_on_all_cpus() can be skipped. 2752 */ 2753 if (!panic) 2754 wbinvd_on_all_cpus(); 2755 2756 __snp_free_firmware_pages(virt_to_page(sev_es_tmr), 2757 get_order(sev_es_tmr_size), 2758 true); 2759 sev_es_tmr = NULL; 2760 } 2761 2762 if (sev_init_ex_buffer) { 2763 __snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer), 2764 get_order(NV_LENGTH), 2765 true); 2766 sev_init_ex_buffer = NULL; 2767 } 2768 2769 __sev_snp_shutdown_locked(&error, panic); 2770 } 2771 2772 static void sev_firmware_shutdown(struct sev_device *sev) 2773 { 2774 /* 2775 * Calling without sev_cmd_mutex held as TSM will likely try disconnecting 2776 * IDE and this ends up calling sev_do_cmd() which locks sev_cmd_mutex. 2777 */ 2778 if (sev->tio_status) 2779 sev_tsm_uninit(sev); 2780 2781 mutex_lock(&sev_cmd_mutex); 2782 2783 __sev_firmware_shutdown(sev, false); 2784 2785 kfree(sev->tio_status); 2786 sev->tio_status = NULL; 2787 2788 mutex_unlock(&sev_cmd_mutex); 2789 } 2790 2791 void sev_platform_shutdown(void) 2792 { 2793 if (!psp_master || !psp_master->sev_data) 2794 return; 2795 2796 sev_firmware_shutdown(psp_master->sev_data); 2797 } 2798 EXPORT_SYMBOL_GPL(sev_platform_shutdown); 2799 2800 u64 sev_get_snp_policy_bits(void) 2801 { 2802 struct psp_device *psp = psp_master; 2803 struct sev_device *sev; 2804 u64 policy_bits; 2805 2806 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) 2807 return 0; 2808 2809 if (!psp || !psp->sev_data) 2810 return 0; 2811 2812 sev = psp->sev_data; 2813 2814 policy_bits = SNP_POLICY_MASK_BASE; 2815 2816 if (sev->snp_plat_status.feature_info) { 2817 if (sev->snp_feat_info_0.ecx & SNP_RAPL_DISABLE_SUPPORTED) 2818 policy_bits |= SNP_POLICY_MASK_RAPL_DIS; 2819 2820 if (sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) 2821 policy_bits |= SNP_POLICY_MASK_CIPHERTEXT_HIDING_DRAM; 2822 2823 if (sev->snp_feat_info_0.ecx & SNP_AES_256_XTS_POLICY_SUPPORTED) 2824 policy_bits |= SNP_POLICY_MASK_MEM_AES_256_XTS; 2825 2826 if (sev->snp_feat_info_0.ecx & SNP_CXL_ALLOW_POLICY_SUPPORTED) 2827 policy_bits |= SNP_POLICY_MASK_CXL_ALLOW; 2828 2829 if (sev_version_greater_or_equal(1, 58)) 2830 policy_bits |= SNP_POLICY_MASK_PAGE_SWAP_DISABLE; 2831 } 2832 2833 return policy_bits; 2834 } 2835 EXPORT_SYMBOL_GPL(sev_get_snp_policy_bits); 2836 2837 void sev_dev_destroy(struct psp_device *psp) 2838 { 2839 struct sev_device *sev = psp->sev_data; 2840 2841 if (!sev) 2842 return; 2843 2844 sev_firmware_shutdown(sev); 2845 2846 if (sev->misc) 2847 kref_put(&misc_dev->refcount, sev_exit); 2848 2849 psp_clear_sev_irq_handler(psp); 2850 } 2851 2852 static int snp_shutdown_on_panic(struct notifier_block *nb, 2853 unsigned long reason, void *arg) 2854 { 2855 struct sev_device *sev = psp_master->sev_data; 2856 2857 /* 2858 * If sev_cmd_mutex is already acquired, then it's likely 2859 * another PSP command is in flight and issuing a shutdown 2860 * would fail in unexpected ways. Rather than create even 2861 * more confusion during a panic, just bail out here. 2862 */ 2863 if (mutex_is_locked(&sev_cmd_mutex)) 2864 return NOTIFY_DONE; 2865 2866 __sev_firmware_shutdown(sev, true); 2867 2868 return NOTIFY_DONE; 2869 } 2870 2871 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd, 2872 void *data, int *error) 2873 { 2874 if (!filep || filep->f_op != &sev_fops) 2875 return -EBADF; 2876 2877 return sev_do_cmd(cmd, data, error); 2878 } 2879 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user); 2880 2881 void sev_pci_init(void) 2882 { 2883 struct sev_device *sev = psp_master->sev_data; 2884 u8 api_major, api_minor, build; 2885 2886 if (!sev) 2887 return; 2888 2889 psp_timeout = psp_probe_timeout; 2890 2891 if (sev_get_api_version()) 2892 goto err; 2893 2894 api_major = sev->api_major; 2895 api_minor = sev->api_minor; 2896 build = sev->build; 2897 2898 if (sev_update_firmware(sev->dev) == 0) 2899 sev_get_api_version(); 2900 2901 if (api_major != sev->api_major || api_minor != sev->api_minor || 2902 build != sev->build) 2903 dev_info(sev->dev, "SEV firmware updated from %d.%d.%d to %d.%d.%d\n", 2904 api_major, api_minor, build, 2905 sev->api_major, sev->api_minor, sev->build); 2906 2907 return; 2908 2909 err: 2910 sev_dev_destroy(psp_master); 2911 2912 psp_master->sev_data = NULL; 2913 } 2914 2915 void sev_pci_exit(void) 2916 { 2917 struct sev_device *sev = psp_master->sev_data; 2918 2919 if (!sev) 2920 return; 2921 2922 sev_firmware_shutdown(sev); 2923 } 2924