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
sev_version_greater_or_equal(u8 maj,u8 min)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
sev_irq_handler(int irq,void * data,unsigned int status)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
sev_wait_cmd_ioc(struct sev_device * sev,unsigned int * reg,unsigned int timeout)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
sev_cmd_buffer_len(int cmd)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
open_file_as_root(const char * filename,int flags,umode_t mode)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
sev_read_init_ex_file(void)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
sev_write_init_ex_file(void)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
sev_write_init_ex_file_if_required(int cmd_id)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
snp_reclaim_pages(unsigned long paddr,unsigned int npages,bool locked)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
rmp_mark_pages_firmware(unsigned long paddr,unsigned int npages,bool locked)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
__snp_alloc_firmware_pages(gfp_t gfp_mask,int order,bool locked)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
snp_alloc_firmware_page(gfp_t gfp_mask)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
__snp_free_firmware_pages(struct page * page,int order,bool locked)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
snp_free_firmware_page(void * addr)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
sev_fw_alloc(unsigned long len)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 */
snp_populate_cmd_buf_desc_list(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)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
snp_map_cmd_buf_desc(struct cmd_buf_desc * desc)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
snp_unmap_cmd_buf_desc(struct cmd_buf_desc * desc)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
snp_map_cmd_buf_desc_list(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)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
snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc * desc_list)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
sev_cmd_buf_writable(int cmd)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. */
snp_legacy_handling_needed(int cmd)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
snp_prep_cmd_buf(int cmd,void * cmd_buf,struct cmd_buf_desc * desc_list)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
snp_reclaim_cmd_buf(int cmd,void * cmd_buf)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
__sev_do_cmd_locked(int cmd,void * data,int * psp_ret)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
sev_do_cmd(int cmd,void * data,int * psp_ret)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
__sev_init_locked(int * error)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
__sev_init_ex_locked(int * error)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
__sev_do_init_locked(int * psp_ret)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 */
snp_hv_fixed_pages_state_update(struct sev_device * sev,enum snp_hv_fixed_pages_state page_state)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 */
snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages)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
snp_free_hv_fixed_pages(struct page * page)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
snp_add_hv_fixed_pages(struct sev_device * sev,struct sev_data_range_list * range_list)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
snp_leak_hv_fixed_pages(void)1220 static void snp_leak_hv_fixed_pages(void)
1221 {
1222 struct snp_hv_fixed_pages_entry *entry, *nentry;
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_safe(entry, nentry, &snp_hv_fixed_pages, list) {
1231 if (entry->free && entry->page_state != HV_FIXED)
1232 __free_pages(entry->page, entry->order);
1233 else
1234 __snp_leak_pages(page_to_pfn(entry->page),
1235 1 << entry->order, false);
1236
1237 list_del(&entry->list);
1238 kfree(entry);
1239 }
1240 }
1241
sev_is_snp_ciphertext_hiding_supported(void)1242 bool sev_is_snp_ciphertext_hiding_supported(void)
1243 {
1244 struct psp_device *psp = psp_master;
1245 struct sev_device *sev;
1246
1247 if (!psp || !psp->sev_data)
1248 return false;
1249
1250 sev = psp->sev_data;
1251
1252 /*
1253 * Feature information indicates if CipherTextHiding feature is
1254 * supported by the SEV firmware and additionally platform status
1255 * indicates if CipherTextHiding feature is enabled in the
1256 * Platform BIOS.
1257 */
1258 return ((sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) &&
1259 sev->snp_plat_status.ciphertext_hiding_cap);
1260 }
1261 EXPORT_SYMBOL_GPL(sev_is_snp_ciphertext_hiding_supported);
1262
snp_get_platform_data(struct sev_device * sev,int * error)1263 static int snp_get_platform_data(struct sev_device *sev, int *error)
1264 {
1265 struct sev_data_snp_feature_info snp_feat_info;
1266 struct snp_feature_info *feat_info;
1267 struct sev_data_snp_addr buf;
1268 struct page *page;
1269 int rc;
1270
1271 /*
1272 * This function is expected to be called before SNP is
1273 * initialized.
1274 */
1275 if (sev->snp_initialized)
1276 return -EINVAL;
1277
1278 buf.address = __psp_pa(&sev->snp_plat_status);
1279 rc = sev_do_cmd(SEV_CMD_SNP_PLATFORM_STATUS, &buf, error);
1280 if (rc) {
1281 dev_err(sev->dev, "SNP PLATFORM_STATUS command failed, ret = %d, error = %#x\n",
1282 rc, *error);
1283 return rc;
1284 }
1285
1286 sev->api_major = sev->snp_plat_status.api_major;
1287 sev->api_minor = sev->snp_plat_status.api_minor;
1288 sev->build = sev->snp_plat_status.build_id;
1289
1290 /*
1291 * Do feature discovery of the currently loaded firmware,
1292 * and cache feature information from CPUID 0x8000_0024,
1293 * sub-function 0.
1294 */
1295 if (!sev->snp_plat_status.feature_info)
1296 return 0;
1297
1298 /*
1299 * Use dynamically allocated structure for the SNP_FEATURE_INFO
1300 * command to ensure structure is 8-byte aligned, and does not
1301 * cross a page boundary.
1302 */
1303 page = alloc_page(GFP_KERNEL);
1304 if (!page)
1305 return -ENOMEM;
1306
1307 feat_info = page_address(page);
1308 snp_feat_info.length = sizeof(snp_feat_info);
1309 snp_feat_info.ecx_in = 0;
1310 snp_feat_info.feature_info_paddr = __psp_pa(feat_info);
1311
1312 rc = sev_do_cmd(SEV_CMD_SNP_FEATURE_INFO, &snp_feat_info, error);
1313 if (!rc)
1314 sev->snp_feat_info_0 = *feat_info;
1315 else
1316 dev_err(sev->dev, "SNP FEATURE_INFO command failed, ret = %d, error = %#x\n",
1317 rc, *error);
1318
1319 __free_page(page);
1320
1321 return rc;
1322 }
1323
snp_filter_reserved_mem_regions(struct resource * rs,void * arg)1324 static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg)
1325 {
1326 struct sev_data_range_list *range_list = arg;
1327 struct sev_data_range *range = &range_list->ranges[range_list->num_elements];
1328 size_t size;
1329
1330 /*
1331 * Ensure the list of HV_FIXED pages that will be passed to firmware
1332 * do not exceed the page-sized argument buffer.
1333 */
1334 if ((range_list->num_elements * sizeof(struct sev_data_range) +
1335 sizeof(struct sev_data_range_list)) > PAGE_SIZE)
1336 return -E2BIG;
1337
1338 switch (rs->desc) {
1339 case E820_TYPE_RESERVED:
1340 case E820_TYPE_PMEM:
1341 case E820_TYPE_ACPI:
1342 range->base = rs->start & PAGE_MASK;
1343 size = PAGE_ALIGN((rs->end + 1) - rs->start);
1344 range->page_count = size >> PAGE_SHIFT;
1345 range_list->num_elements++;
1346 break;
1347 default:
1348 break;
1349 }
1350
1351 return 0;
1352 }
1353
__sev_snp_init_locked(int * error,unsigned int max_snp_asid)1354 static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid)
1355 {
1356 struct sev_data_range_list *snp_range_list __free(kfree) = NULL;
1357 struct psp_device *psp = psp_master;
1358 struct sev_data_snp_init_ex data;
1359 struct sev_device *sev;
1360 void *arg = &data;
1361 int cmd, rc = 0;
1362
1363 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
1364 return -ENODEV;
1365
1366 sev = psp->sev_data;
1367
1368 if (sev->snp_initialized)
1369 return 0;
1370
1371 if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) {
1372 dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n",
1373 SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR);
1374 return -EOPNOTSUPP;
1375 }
1376
1377 snp_prepare();
1378
1379 /*
1380 * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list
1381 * of system physical address ranges to convert into HV-fixed page
1382 * states during the RMP initialization. For instance, the memory that
1383 * UEFI reserves should be included in the that list. This allows system
1384 * components that occasionally write to memory (e.g. logging to UEFI
1385 * reserved regions) to not fail due to RMP initialization and SNP
1386 * enablement.
1387 *
1388 */
1389 if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) {
1390 bool tio_supp = !!(sev->snp_feat_info_0.ebx & SNP_SEV_TIO_SUPPORTED);
1391
1392 /*
1393 * Firmware checks that the pages containing the ranges enumerated
1394 * in the RANGES structure are either in the default page state or in the
1395 * firmware page state.
1396 */
1397 snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL);
1398 if (!snp_range_list) {
1399 dev_err(sev->dev,
1400 "SEV: SNP_INIT_EX range list memory allocation failed\n");
1401 return -ENOMEM;
1402 }
1403
1404 /*
1405 * Retrieve all reserved memory regions from the e820 memory map
1406 * to be setup as HV-fixed pages.
1407 */
1408 rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0,
1409 snp_range_list, snp_filter_reserved_mem_regions);
1410 if (rc) {
1411 dev_err(sev->dev,
1412 "SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc);
1413 return rc;
1414 }
1415
1416 /*
1417 * Add HV_Fixed pages from other PSP sub-devices, such as SFS to the
1418 * HV_Fixed page list.
1419 */
1420 snp_add_hv_fixed_pages(sev, snp_range_list);
1421
1422 memset(&data, 0, sizeof(data));
1423
1424 if (max_snp_asid) {
1425 data.ciphertext_hiding_en = 1;
1426 data.max_snp_asid = max_snp_asid;
1427 }
1428
1429 data.init_rmp = 1;
1430 data.list_paddr_en = 1;
1431 data.list_paddr = __psp_pa(snp_range_list);
1432
1433 data.tio_en = tio_supp && sev_tio_enabled && amd_iommu_sev_tio_supported();
1434
1435 /*
1436 * When psp_init_on_probe is disabled, the userspace calling
1437 * SEV ioctl can inadvertently shut down SNP and SEV-TIO causing
1438 * unexpected state loss.
1439 */
1440 if (data.tio_en && !psp_init_on_probe)
1441 dev_warn(sev->dev, "SEV-TIO as incompatible with psp_init_on_probe=0\n");
1442
1443 cmd = SEV_CMD_SNP_INIT_EX;
1444 } else {
1445 cmd = SEV_CMD_SNP_INIT;
1446 arg = NULL;
1447 }
1448
1449 /*
1450 * The following sequence must be issued before launching the first SNP
1451 * guest to ensure all dirty cache lines are flushed, including from
1452 * updates to the RMP table itself via the RMPUPDATE instruction:
1453 *
1454 * - WBINVD on all running CPUs
1455 * - SEV_CMD_SNP_INIT[_EX] firmware command
1456 * - WBINVD on all running CPUs
1457 * - SEV_CMD_SNP_DF_FLUSH firmware command
1458 */
1459 wbinvd_on_all_cpus();
1460
1461 rc = __sev_do_cmd_locked(cmd, arg, error);
1462 if (rc) {
1463 dev_err(sev->dev, "SEV-SNP: %s failed rc %d, error %#x\n",
1464 cmd == SEV_CMD_SNP_INIT_EX ? "SNP_INIT_EX" : "SNP_INIT",
1465 rc, *error);
1466 return rc;
1467 }
1468
1469 /* Prepare for first SNP guest launch after INIT. */
1470 wbinvd_on_all_cpus();
1471 rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error);
1472 if (rc) {
1473 dev_err(sev->dev, "SEV-SNP: SNP_DF_FLUSH failed rc %d, error %#x\n",
1474 rc, *error);
1475 return rc;
1476 }
1477
1478 snp_hv_fixed_pages_state_update(sev, HV_FIXED);
1479 sev->snp_initialized = true;
1480 dev_dbg(sev->dev, "SEV-SNP firmware initialized, SEV-TIO is %s\n",
1481 data.tio_en ? "enabled" : "disabled");
1482
1483 dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major,
1484 sev->api_minor, sev->build);
1485
1486 atomic_notifier_chain_register(&panic_notifier_list,
1487 &snp_panic_notifier);
1488
1489 if (data.tio_en) {
1490 /*
1491 * This executes with the sev_cmd_mutex held so down the stack
1492 * snp_reclaim_pages(locked=false) might be needed (which is extremely
1493 * unlikely) but will cause a deadlock.
1494 * Instead of exporting __snp_alloc_firmware_pages(), allocate a page
1495 * for this one call here.
1496 */
1497 void *tio_status = page_address(__snp_alloc_firmware_pages(
1498 GFP_KERNEL_ACCOUNT | __GFP_ZERO, 0, true));
1499
1500 if (tio_status) {
1501 sev_tsm_init_locked(sev, tio_status);
1502 __snp_free_firmware_pages(virt_to_page(tio_status), 0, true);
1503 }
1504 }
1505
1506 sev_es_tmr_size = SNP_TMR_SIZE;
1507
1508 return 0;
1509 }
1510
__sev_platform_init_handle_tmr(struct sev_device * sev)1511 static void __sev_platform_init_handle_tmr(struct sev_device *sev)
1512 {
1513 if (sev_es_tmr)
1514 return;
1515
1516 /* Obtain the TMR memory area for SEV-ES use */
1517 sev_es_tmr = sev_fw_alloc(sev_es_tmr_size);
1518 if (sev_es_tmr) {
1519 /* Must flush the cache before giving it to the firmware */
1520 if (!sev->snp_initialized)
1521 clflush_cache_range(sev_es_tmr, sev_es_tmr_size);
1522 } else {
1523 dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1524 }
1525 }
1526
1527 /*
1528 * If an init_ex_path is provided allocate a buffer for the file and
1529 * read in the contents. Additionally, if SNP is initialized, convert
1530 * the buffer pages to firmware pages.
1531 */
__sev_platform_init_handle_init_ex_path(struct sev_device * sev)1532 static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev)
1533 {
1534 struct page *page;
1535 int rc;
1536
1537 if (!init_ex_path)
1538 return 0;
1539
1540 if (sev_init_ex_buffer)
1541 return 0;
1542
1543 page = alloc_pages(GFP_KERNEL, get_order(NV_LENGTH));
1544 if (!page) {
1545 dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n");
1546 return -ENOMEM;
1547 }
1548
1549 sev_init_ex_buffer = page_address(page);
1550
1551 rc = sev_read_init_ex_file();
1552 if (rc)
1553 return rc;
1554
1555 /* If SEV-SNP is initialized, transition to firmware page. */
1556 if (sev->snp_initialized) {
1557 unsigned long npages;
1558
1559 npages = 1UL << get_order(NV_LENGTH);
1560 if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, false)) {
1561 dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n");
1562 return -ENOMEM;
1563 }
1564 }
1565
1566 return 0;
1567 }
1568
__sev_platform_init_locked(int * error)1569 static int __sev_platform_init_locked(int *error)
1570 {
1571 int rc, psp_ret, dfflush_error;
1572 struct sev_device *sev;
1573
1574 psp_ret = dfflush_error = SEV_RET_NO_FW_CALL;
1575
1576 if (!psp_master || !psp_master->sev_data)
1577 return -ENODEV;
1578
1579 sev = psp_master->sev_data;
1580
1581 if (sev->sev_plat_status.state == SEV_STATE_INIT)
1582 return 0;
1583
1584 __sev_platform_init_handle_tmr(sev);
1585
1586 rc = __sev_platform_init_handle_init_ex_path(sev);
1587 if (rc)
1588 return rc;
1589
1590 rc = __sev_do_init_locked(&psp_ret);
1591 if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) {
1592 /*
1593 * Initialization command returned an integrity check failure
1594 * status code, meaning that firmware load and validation of SEV
1595 * related persistent data has failed. Retrying the
1596 * initialization function should succeed by replacing the state
1597 * with a reset state.
1598 */
1599 dev_err(sev->dev,
1600 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state.");
1601 rc = __sev_do_init_locked(&psp_ret);
1602 }
1603
1604 if (error)
1605 *error = psp_ret;
1606
1607 if (rc) {
1608 dev_err(sev->dev, "SEV: %s failed %#x, rc %d\n",
1609 sev_init_ex_buffer ? "INIT_EX" : "INIT", psp_ret, rc);
1610 return rc;
1611 }
1612
1613 sev->sev_plat_status.state = SEV_STATE_INIT;
1614
1615 /* Prepare for first SEV guest launch after INIT */
1616 wbinvd_on_all_cpus();
1617 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, &dfflush_error);
1618 if (rc) {
1619 dev_err(sev->dev, "SEV: DF_FLUSH failed %#x, rc %d\n",
1620 dfflush_error, rc);
1621 return rc;
1622 }
1623
1624 dev_dbg(sev->dev, "SEV firmware initialized\n");
1625
1626 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1627 sev->api_minor, sev->build);
1628
1629 return 0;
1630 }
1631
_sev_platform_init_locked(struct sev_platform_init_args * args)1632 static int _sev_platform_init_locked(struct sev_platform_init_args *args)
1633 {
1634 struct sev_device *sev;
1635 int rc;
1636
1637 if (!psp_master || !psp_master->sev_data)
1638 return -ENODEV;
1639
1640 /*
1641 * Skip SNP/SEV initialization under a kdump kernel as SEV/SNP
1642 * may already be initialized in the previous kernel. Since no
1643 * SNP/SEV guests are run under a kdump kernel, there is no
1644 * need to initialize SNP or SEV during kdump boot.
1645 */
1646 if (is_kdump_kernel())
1647 return 0;
1648
1649 sev = psp_master->sev_data;
1650
1651 if (sev->sev_plat_status.state == SEV_STATE_INIT)
1652 return 0;
1653
1654 rc = __sev_snp_init_locked(&args->error, args->max_snp_asid);
1655 if (rc && rc != -ENODEV)
1656 return rc;
1657
1658 /* Defer legacy SEV/SEV-ES support if allowed by caller/module. */
1659 if (args->probe && !psp_init_on_probe)
1660 return 0;
1661
1662 return __sev_platform_init_locked(&args->error);
1663 }
1664
sev_platform_init(struct sev_platform_init_args * args)1665 int sev_platform_init(struct sev_platform_init_args *args)
1666 {
1667 int rc;
1668
1669 mutex_lock(&sev_cmd_mutex);
1670 rc = _sev_platform_init_locked(args);
1671 mutex_unlock(&sev_cmd_mutex);
1672
1673 return rc;
1674 }
1675 EXPORT_SYMBOL_GPL(sev_platform_init);
1676
__sev_platform_shutdown_locked(int * error)1677 static int __sev_platform_shutdown_locked(int *error)
1678 {
1679 struct psp_device *psp = psp_master;
1680 struct sev_device *sev;
1681 int ret;
1682
1683 if (!psp || !psp->sev_data)
1684 return 0;
1685
1686 sev = psp->sev_data;
1687
1688 if (sev->sev_plat_status.state == SEV_STATE_UNINIT)
1689 return 0;
1690
1691 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
1692 if (ret) {
1693 dev_err(sev->dev, "SEV: failed to SHUTDOWN error %#x, rc %d\n",
1694 *error, ret);
1695 return ret;
1696 }
1697
1698 sev->sev_plat_status.state = SEV_STATE_UNINIT;
1699 dev_dbg(sev->dev, "SEV firmware shutdown\n");
1700
1701 return ret;
1702 }
1703
sev_get_platform_state(int * state,int * error)1704 static int sev_get_platform_state(int *state, int *error)
1705 {
1706 struct sev_user_data_status data;
1707 int rc;
1708
1709 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
1710 if (rc)
1711 return rc;
1712
1713 *state = data.state;
1714 return rc;
1715 }
1716
sev_move_to_init_state(struct sev_issue_cmd * argp,bool * shutdown_required)1717 static int sev_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
1718 {
1719 struct sev_platform_init_args init_args = {0};
1720 int rc;
1721
1722 rc = _sev_platform_init_locked(&init_args);
1723 if (rc) {
1724 argp->error = SEV_RET_INVALID_PLATFORM_STATE;
1725 return rc;
1726 }
1727
1728 *shutdown_required = true;
1729
1730 return 0;
1731 }
1732
snp_move_to_init_state(struct sev_issue_cmd * argp,bool * shutdown_required)1733 static int snp_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
1734 {
1735 int error, rc;
1736
1737 rc = __sev_snp_init_locked(&error, 0);
1738 if (rc) {
1739 argp->error = SEV_RET_INVALID_PLATFORM_STATE;
1740 return rc;
1741 }
1742
1743 *shutdown_required = true;
1744
1745 return 0;
1746 }
1747
sev_ioctl_do_reset(struct sev_issue_cmd * argp,bool writable)1748 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
1749 {
1750 int state, rc;
1751
1752 if (!writable)
1753 return -EPERM;
1754
1755 /*
1756 * The SEV spec requires that FACTORY_RESET must be issued in
1757 * UNINIT state. Before we go further lets check if any guest is
1758 * active.
1759 *
1760 * If FW is in WORKING state then deny the request otherwise issue
1761 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
1762 *
1763 */
1764 rc = sev_get_platform_state(&state, &argp->error);
1765 if (rc)
1766 return rc;
1767
1768 if (state == SEV_STATE_WORKING)
1769 return -EBUSY;
1770
1771 if (state == SEV_STATE_INIT) {
1772 rc = __sev_platform_shutdown_locked(&argp->error);
1773 if (rc)
1774 return rc;
1775 }
1776
1777 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
1778 }
1779
sev_ioctl_do_platform_status(struct sev_issue_cmd * argp)1780 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
1781 {
1782 struct sev_user_data_status data;
1783 int ret;
1784
1785 memset(&data, 0, sizeof(data));
1786
1787 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
1788 if (ret)
1789 return ret;
1790
1791 if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
1792 ret = -EFAULT;
1793
1794 return ret;
1795 }
1796
sev_ioctl_do_pek_pdh_gen(int cmd,struct sev_issue_cmd * argp,bool writable)1797 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
1798 {
1799 struct sev_device *sev = psp_master->sev_data;
1800 bool shutdown_required = false;
1801 int rc;
1802
1803 if (!writable)
1804 return -EPERM;
1805
1806 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
1807 rc = sev_move_to_init_state(argp, &shutdown_required);
1808 if (rc)
1809 return rc;
1810 }
1811
1812 rc = __sev_do_cmd_locked(cmd, NULL, &argp->error);
1813
1814 if (shutdown_required)
1815 __sev_firmware_shutdown(sev, false);
1816
1817 return rc;
1818 }
1819
sev_ioctl_do_pek_csr(struct sev_issue_cmd * argp,bool writable)1820 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
1821 {
1822 struct sev_device *sev = psp_master->sev_data;
1823 struct sev_user_data_pek_csr input;
1824 bool shutdown_required = false;
1825 struct sev_data_pek_csr data;
1826 void __user *input_address;
1827 void *blob = NULL;
1828 int ret;
1829
1830 if (!writable)
1831 return -EPERM;
1832
1833 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
1834 return -EFAULT;
1835
1836 memset(&data, 0, sizeof(data));
1837
1838 /* userspace wants to query CSR length */
1839 if (!input.address || !input.length)
1840 goto cmd;
1841
1842 /* allocate a physically contiguous buffer to store the CSR blob */
1843 input_address = (void __user *)input.address;
1844 if (input.length > SEV_FW_BLOB_MAX_SIZE)
1845 return -EFAULT;
1846
1847 blob = kzalloc(input.length, GFP_KERNEL);
1848 if (!blob)
1849 return -ENOMEM;
1850
1851 data.address = __psp_pa(blob);
1852 data.len = input.length;
1853
1854 cmd:
1855 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
1856 ret = sev_move_to_init_state(argp, &shutdown_required);
1857 if (ret)
1858 goto e_free_blob;
1859 }
1860
1861 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
1862
1863 /* If we query the CSR length, FW responded with expected data. */
1864 input.length = data.len;
1865
1866 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
1867 ret = -EFAULT;
1868 goto e_free_blob;
1869 }
1870
1871 if (blob) {
1872 if (copy_to_user(input_address, blob, input.length))
1873 ret = -EFAULT;
1874 }
1875
1876 e_free_blob:
1877 if (shutdown_required)
1878 __sev_firmware_shutdown(sev, false);
1879
1880 kfree(blob);
1881 return ret;
1882 }
1883
psp_copy_user_blob(u64 uaddr,u32 len)1884 void *psp_copy_user_blob(u64 uaddr, u32 len)
1885 {
1886 if (!uaddr || !len)
1887 return ERR_PTR(-EINVAL);
1888
1889 /* verify that blob length does not exceed our limit */
1890 if (len > SEV_FW_BLOB_MAX_SIZE)
1891 return ERR_PTR(-EINVAL);
1892
1893 return memdup_user((void __user *)uaddr, len);
1894 }
1895 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
1896
sev_get_api_version(void)1897 static int sev_get_api_version(void)
1898 {
1899 struct sev_device *sev = psp_master->sev_data;
1900 struct sev_user_data_status status;
1901 int error = 0, ret;
1902
1903 /*
1904 * Cache SNP platform status and SNP feature information
1905 * if SNP is available.
1906 */
1907 if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) {
1908 ret = snp_get_platform_data(sev, &error);
1909 if (ret)
1910 return 1;
1911 }
1912
1913 ret = sev_platform_status(&status, &error);
1914 if (ret) {
1915 dev_err(sev->dev,
1916 "SEV: failed to get status. Error: %#x\n", error);
1917 return 1;
1918 }
1919
1920 /* Cache SEV platform status */
1921 sev->sev_plat_status = status;
1922
1923 sev->api_major = status.api_major;
1924 sev->api_minor = status.api_minor;
1925 sev->build = status.build;
1926
1927 return 0;
1928 }
1929
sev_get_firmware(struct device * dev,const struct firmware ** firmware)1930 static int sev_get_firmware(struct device *dev,
1931 const struct firmware **firmware)
1932 {
1933 char fw_name_specific[SEV_FW_NAME_SIZE];
1934 char fw_name_subset[SEV_FW_NAME_SIZE];
1935
1936 snprintf(fw_name_specific, sizeof(fw_name_specific),
1937 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
1938 boot_cpu_data.x86, boot_cpu_data.x86_model);
1939
1940 snprintf(fw_name_subset, sizeof(fw_name_subset),
1941 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
1942 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
1943
1944 /* Check for SEV FW for a particular model.
1945 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
1946 *
1947 * or
1948 *
1949 * Check for SEV FW common to a subset of models.
1950 * Ex. amd_sev_fam17h_model0xh.sbin for
1951 * Family 17h Model 00h -- Family 17h Model 0Fh
1952 *
1953 * or
1954 *
1955 * Fall-back to using generic name: sev.fw
1956 */
1957 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
1958 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
1959 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
1960 return 0;
1961
1962 return -ENOENT;
1963 }
1964
1965 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
sev_update_firmware(struct device * dev)1966 static int sev_update_firmware(struct device *dev)
1967 {
1968 struct sev_data_download_firmware data;
1969 const struct firmware *firmware;
1970 int ret, error, order;
1971 struct page *p;
1972 void *fw_blob;
1973
1974 if (!sev_version_greater_or_equal(0, 15)) {
1975 dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n");
1976 return -1;
1977 }
1978
1979 if (sev_get_firmware(dev, &firmware) == -ENOENT) {
1980 dev_dbg(dev, "No SEV firmware file present\n");
1981 return -1;
1982 }
1983
1984 order = get_order(firmware->size);
1985 p = alloc_pages(GFP_KERNEL, order);
1986 if (!p) {
1987 ret = -1;
1988 goto fw_err;
1989 }
1990
1991 /*
1992 * Copy firmware data to a kernel allocated contiguous
1993 * memory region.
1994 */
1995 fw_blob = page_address(p);
1996 memcpy(fw_blob, firmware->data, firmware->size);
1997
1998 data.address = __psp_pa(fw_blob);
1999 data.len = firmware->size;
2000
2001 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, &data, &error);
2002
2003 /*
2004 * A quirk for fixing the committed TCB version, when upgrading from
2005 * earlier firmware version than 1.50.
2006 */
2007 if (!ret && !sev_version_greater_or_equal(1, 50))
2008 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, &data, &error);
2009
2010 if (ret)
2011 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
2012
2013 __free_pages(p, order);
2014
2015 fw_err:
2016 release_firmware(firmware);
2017
2018 return ret;
2019 }
2020
__sev_snp_shutdown_locked(int * error,bool panic)2021 static int __sev_snp_shutdown_locked(int *error, bool panic)
2022 {
2023 struct psp_device *psp = psp_master;
2024 struct sev_device *sev;
2025 struct sev_data_snp_shutdown_ex data;
2026 int ret;
2027
2028 if (!psp || !psp->sev_data)
2029 return 0;
2030
2031 sev = psp->sev_data;
2032
2033 if (!sev->snp_initialized)
2034 return 0;
2035
2036 memset(&data, 0, sizeof(data));
2037 data.len = sizeof(data);
2038 data.iommu_snp_shutdown = 1;
2039 if (sev->snp_feat_info_0.ecx & SNP_X86_SHUTDOWN_SUPPORTED)
2040 data.x86_snp_shutdown = 1;
2041
2042 /*
2043 * If invoked during panic handling, local interrupts are disabled
2044 * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called.
2045 * In that case, a wbinvd() is done on remote CPUs via the NMI
2046 * callback, so only a local wbinvd() is needed here.
2047 */
2048 if (!panic)
2049 wbinvd_on_all_cpus();
2050 else
2051 wbinvd();
2052
2053 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error);
2054 /* SHUTDOWN may require DF_FLUSH */
2055 if (*error == SEV_RET_DFFLUSH_REQUIRED) {
2056 int dfflush_error = SEV_RET_NO_FW_CALL;
2057
2058 ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, &dfflush_error);
2059 if (ret) {
2060 dev_err(sev->dev, "SEV-SNP DF_FLUSH failed, ret = %d, error = %#x\n",
2061 ret, dfflush_error);
2062 return ret;
2063 }
2064 /* reissue the shutdown command */
2065 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data,
2066 error);
2067 }
2068 if (ret) {
2069 dev_err(sev->dev, "SEV-SNP firmware shutdown failed, rc %d, error %#x\n",
2070 ret, *error);
2071 return ret;
2072 }
2073
2074 if (data.x86_snp_shutdown) {
2075 if (!panic)
2076 snp_shutdown();
2077 snp_hv_fixed_pages_state_update(sev, ALLOCATED);
2078 } else {
2079 /*
2080 * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP
2081 * enforcement by the IOMMU and also transitions all pages
2082 * associated with the IOMMU to the Reclaim state.
2083 * Firmware was transitioning the IOMMU pages to Hypervisor state
2084 * before version 1.53. But, accounting for the number of assigned
2085 * 4kB pages in a 2M page was done incorrectly by not transitioning
2086 * to the Reclaim state. This resulted in RMP #PF when later accessing
2087 * the 2M page containing those pages during kexec boot. Hence, the
2088 * firmware now transitions these pages to Reclaim state and hypervisor
2089 * needs to transition these pages to shared state. SNP Firmware
2090 * version 1.53 and above are needed for kexec boot.
2091 */
2092 ret = amd_iommu_snp_disable();
2093 if (ret) {
2094 dev_err(sev->dev, "SNP IOMMU shutdown failed\n");
2095 return ret;
2096 }
2097 }
2098
2099 snp_leak_hv_fixed_pages();
2100 sev->snp_initialized = false;
2101 dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n");
2102
2103 /*
2104 * __sev_snp_shutdown_locked() deadlocks when it tries to unregister
2105 * itself during panic as the panic notifier is called with RCU read
2106 * lock held and notifier unregistration does RCU synchronization.
2107 */
2108 if (!panic)
2109 atomic_notifier_chain_unregister(&panic_notifier_list,
2110 &snp_panic_notifier);
2111
2112 /* Reset TMR size back to default */
2113 sev_es_tmr_size = SEV_TMR_SIZE;
2114
2115 return ret;
2116 }
2117
sev_ioctl_do_pek_import(struct sev_issue_cmd * argp,bool writable)2118 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
2119 {
2120 struct sev_device *sev = psp_master->sev_data;
2121 struct sev_user_data_pek_cert_import input;
2122 struct sev_data_pek_cert_import data;
2123 bool shutdown_required = false;
2124 void *pek_blob, *oca_blob;
2125 int ret;
2126
2127 if (!writable)
2128 return -EPERM;
2129
2130 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2131 return -EFAULT;
2132
2133 /* copy PEK certificate blobs from userspace */
2134 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
2135 if (IS_ERR(pek_blob))
2136 return PTR_ERR(pek_blob);
2137
2138 data.reserved = 0;
2139 data.pek_cert_address = __psp_pa(pek_blob);
2140 data.pek_cert_len = input.pek_cert_len;
2141
2142 /* copy PEK certificate blobs from userspace */
2143 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
2144 if (IS_ERR(oca_blob)) {
2145 ret = PTR_ERR(oca_blob);
2146 goto e_free_pek;
2147 }
2148
2149 data.oca_cert_address = __psp_pa(oca_blob);
2150 data.oca_cert_len = input.oca_cert_len;
2151
2152 /* If platform is not in INIT state then transition it to INIT */
2153 if (sev->sev_plat_status.state != SEV_STATE_INIT) {
2154 ret = sev_move_to_init_state(argp, &shutdown_required);
2155 if (ret)
2156 goto e_free_oca;
2157 }
2158
2159 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
2160
2161 e_free_oca:
2162 if (shutdown_required)
2163 __sev_firmware_shutdown(sev, false);
2164
2165 kfree(oca_blob);
2166 e_free_pek:
2167 kfree(pek_blob);
2168 return ret;
2169 }
2170
sev_ioctl_do_get_id2(struct sev_issue_cmd * argp)2171 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
2172 {
2173 struct sev_user_data_get_id2 input;
2174 struct sev_data_get_id data;
2175 void __user *input_address;
2176 void *id_blob = NULL;
2177 int ret;
2178
2179 /* SEV GET_ID is available from SEV API v0.16 and up */
2180 if (!sev_version_greater_or_equal(0, 16))
2181 return -ENOTSUPP;
2182
2183 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2184 return -EFAULT;
2185
2186 input_address = (void __user *)input.address;
2187
2188 if (input.address && input.length) {
2189 /*
2190 * The length of the ID shouldn't be assumed by software since
2191 * it may change in the future. The allocation size is limited
2192 * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator.
2193 * If the allocation fails, simply return ENOMEM rather than
2194 * warning in the kernel log.
2195 */
2196 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN);
2197 if (!id_blob)
2198 return -ENOMEM;
2199
2200 data.address = __psp_pa(id_blob);
2201 data.len = input.length;
2202 } else {
2203 data.address = 0;
2204 data.len = 0;
2205 }
2206
2207 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
2208
2209 /*
2210 * Firmware will return the length of the ID value (either the minimum
2211 * required length or the actual length written), return it to the user.
2212 */
2213 input.length = data.len;
2214
2215 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
2216 ret = -EFAULT;
2217 goto e_free;
2218 }
2219
2220 if (id_blob) {
2221 if (copy_to_user(input_address, id_blob, data.len)) {
2222 ret = -EFAULT;
2223 goto e_free;
2224 }
2225 }
2226
2227 e_free:
2228 kfree(id_blob);
2229
2230 return ret;
2231 }
2232
sev_ioctl_do_get_id(struct sev_issue_cmd * argp)2233 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
2234 {
2235 struct sev_data_get_id *data;
2236 u64 data_size, user_size;
2237 void *id_blob, *mem;
2238 int ret;
2239
2240 /* SEV GET_ID available from SEV API v0.16 and up */
2241 if (!sev_version_greater_or_equal(0, 16))
2242 return -ENOTSUPP;
2243
2244 /* SEV FW expects the buffer it fills with the ID to be
2245 * 8-byte aligned. Memory allocated should be enough to
2246 * hold data structure + alignment padding + memory
2247 * where SEV FW writes the ID.
2248 */
2249 data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
2250 user_size = sizeof(struct sev_user_data_get_id);
2251
2252 mem = kzalloc(data_size + user_size, GFP_KERNEL);
2253 if (!mem)
2254 return -ENOMEM;
2255
2256 data = mem;
2257 id_blob = mem + data_size;
2258
2259 data->address = __psp_pa(id_blob);
2260 data->len = user_size;
2261
2262 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
2263 if (!ret) {
2264 if (copy_to_user((void __user *)argp->data, id_blob, data->len))
2265 ret = -EFAULT;
2266 }
2267
2268 kfree(mem);
2269
2270 return ret;
2271 }
2272
sev_ioctl_do_pdh_export(struct sev_issue_cmd * argp,bool writable)2273 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
2274 {
2275 struct sev_device *sev = psp_master->sev_data;
2276 struct sev_user_data_pdh_cert_export input;
2277 void *pdh_blob = NULL, *cert_blob = NULL;
2278 struct sev_data_pdh_cert_export data;
2279 void __user *input_cert_chain_address;
2280 void __user *input_pdh_cert_address;
2281 bool shutdown_required = false;
2282 int ret;
2283
2284 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
2285 return -EFAULT;
2286
2287 memset(&data, 0, sizeof(data));
2288
2289 input_pdh_cert_address = (void __user *)input.pdh_cert_address;
2290 input_cert_chain_address = (void __user *)input.cert_chain_address;
2291
2292 /* Userspace wants to query the certificate length. */
2293 if (!input.pdh_cert_address ||
2294 !input.pdh_cert_len ||
2295 !input.cert_chain_address)
2296 goto cmd;
2297
2298 /* Allocate a physically contiguous buffer to store the PDH blob. */
2299 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
2300 return -EFAULT;
2301
2302 /* Allocate a physically contiguous buffer to store the cert chain blob. */
2303 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
2304 return -EFAULT;
2305
2306 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL);
2307 if (!pdh_blob)
2308 return -ENOMEM;
2309
2310 data.pdh_cert_address = __psp_pa(pdh_blob);
2311 data.pdh_cert_len = input.pdh_cert_len;
2312
2313 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL);
2314 if (!cert_blob) {
2315 ret = -ENOMEM;
2316 goto e_free_pdh;
2317 }
2318
2319 data.cert_chain_address = __psp_pa(cert_blob);
2320 data.cert_chain_len = input.cert_chain_len;
2321
2322 cmd:
2323 /* If platform is not in INIT state then transition it to INIT. */
2324 if (sev->sev_plat_status.state != SEV_STATE_INIT) {
2325 if (!writable) {
2326 ret = -EPERM;
2327 goto e_free_cert;
2328 }
2329 ret = sev_move_to_init_state(argp, &shutdown_required);
2330 if (ret)
2331 goto e_free_cert;
2332 }
2333
2334 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
2335
2336 /* If we query the length, FW responded with expected data. */
2337 input.cert_chain_len = data.cert_chain_len;
2338 input.pdh_cert_len = data.pdh_cert_len;
2339
2340 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
2341 ret = -EFAULT;
2342 goto e_free_cert;
2343 }
2344
2345 if (pdh_blob) {
2346 if (copy_to_user(input_pdh_cert_address,
2347 pdh_blob, input.pdh_cert_len)) {
2348 ret = -EFAULT;
2349 goto e_free_cert;
2350 }
2351 }
2352
2353 if (cert_blob) {
2354 if (copy_to_user(input_cert_chain_address,
2355 cert_blob, input.cert_chain_len))
2356 ret = -EFAULT;
2357 }
2358
2359 e_free_cert:
2360 if (shutdown_required)
2361 __sev_firmware_shutdown(sev, false);
2362
2363 kfree(cert_blob);
2364 e_free_pdh:
2365 kfree(pdh_blob);
2366 return ret;
2367 }
2368
sev_ioctl_do_snp_platform_status(struct sev_issue_cmd * argp)2369 static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp)
2370 {
2371 struct sev_device *sev = psp_master->sev_data;
2372 struct sev_data_snp_addr buf;
2373 struct page *status_page;
2374 void *data;
2375 int ret;
2376
2377 if (!argp->data)
2378 return -EINVAL;
2379
2380 status_page = alloc_page(GFP_KERNEL_ACCOUNT);
2381 if (!status_page)
2382 return -ENOMEM;
2383
2384 data = page_address(status_page);
2385
2386 /*
2387 * SNP_PLATFORM_STATUS can be executed in any SNP state. But if executed
2388 * when SNP has been initialized, the status page must be firmware-owned.
2389 */
2390 if (sev->snp_initialized) {
2391 /*
2392 * Firmware expects the status page to be in Firmware state,
2393 * otherwise it will report an error INVALID_PAGE_STATE.
2394 */
2395 if (rmp_mark_pages_firmware(__pa(data), 1, true)) {
2396 ret = -EFAULT;
2397 goto cleanup;
2398 }
2399 }
2400
2401 buf.address = __psp_pa(data);
2402 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error);
2403
2404 if (sev->snp_initialized) {
2405 /*
2406 * The status page will be in Reclaim state on success, or left
2407 * in Firmware state on failure. Use snp_reclaim_pages() to
2408 * transition either case back to Hypervisor-owned state.
2409 */
2410 if (snp_reclaim_pages(__pa(data), 1, true))
2411 return -EFAULT;
2412 }
2413
2414 if (ret)
2415 goto cleanup;
2416
2417 if (copy_to_user((void __user *)argp->data, data,
2418 sizeof(struct sev_user_data_snp_status)))
2419 ret = -EFAULT;
2420
2421 cleanup:
2422 __free_pages(status_page, 0);
2423 return ret;
2424 }
2425
sev_ioctl_do_snp_commit(struct sev_issue_cmd * argp)2426 static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp)
2427 {
2428 struct sev_device *sev = psp_master->sev_data;
2429 struct sev_data_snp_commit buf;
2430 bool shutdown_required = false;
2431 int ret, error;
2432
2433 if (!sev->snp_initialized) {
2434 ret = snp_move_to_init_state(argp, &shutdown_required);
2435 if (ret)
2436 return ret;
2437 }
2438
2439 buf.len = sizeof(buf);
2440
2441 ret = __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error);
2442
2443 if (shutdown_required)
2444 __sev_snp_shutdown_locked(&error, false);
2445
2446 return ret;
2447 }
2448
sev_ioctl_do_snp_set_config(struct sev_issue_cmd * argp,bool writable)2449 static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable)
2450 {
2451 struct sev_device *sev = psp_master->sev_data;
2452 struct sev_user_data_snp_config config;
2453 bool shutdown_required = false;
2454 int ret, error;
2455
2456 if (!argp->data)
2457 return -EINVAL;
2458
2459 if (!writable)
2460 return -EPERM;
2461
2462 if (copy_from_user(&config, (void __user *)argp->data, sizeof(config)))
2463 return -EFAULT;
2464
2465 if (!sev->snp_initialized) {
2466 ret = snp_move_to_init_state(argp, &shutdown_required);
2467 if (ret)
2468 return ret;
2469 }
2470
2471 ret = __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error);
2472
2473 if (shutdown_required)
2474 __sev_snp_shutdown_locked(&error, false);
2475
2476 return ret;
2477 }
2478
sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd * argp,bool writable)2479 static int sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd *argp, bool writable)
2480 {
2481 struct sev_device *sev = psp_master->sev_data;
2482 struct sev_user_data_snp_vlek_load input;
2483 bool shutdown_required = false;
2484 int ret, error;
2485 void *blob;
2486
2487 if (!argp->data)
2488 return -EINVAL;
2489
2490 if (!writable)
2491 return -EPERM;
2492
2493 if (copy_from_user(&input, u64_to_user_ptr(argp->data), sizeof(input)))
2494 return -EFAULT;
2495
2496 if (input.len != sizeof(input) || input.vlek_wrapped_version != 0)
2497 return -EINVAL;
2498
2499 blob = psp_copy_user_blob(input.vlek_wrapped_address,
2500 sizeof(struct sev_user_data_snp_wrapped_vlek_hashstick));
2501 if (IS_ERR(blob))
2502 return PTR_ERR(blob);
2503
2504 input.vlek_wrapped_address = __psp_pa(blob);
2505
2506 if (!sev->snp_initialized) {
2507 ret = snp_move_to_init_state(argp, &shutdown_required);
2508 if (ret)
2509 goto cleanup;
2510 }
2511
2512 ret = __sev_do_cmd_locked(SEV_CMD_SNP_VLEK_LOAD, &input, &argp->error);
2513
2514 if (shutdown_required)
2515 __sev_snp_shutdown_locked(&error, false);
2516
2517 cleanup:
2518 kfree(blob);
2519
2520 return ret;
2521 }
2522
sev_ioctl(struct file * file,unsigned int ioctl,unsigned long arg)2523 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
2524 {
2525 void __user *argp = (void __user *)arg;
2526 struct sev_issue_cmd input;
2527 int ret = -EFAULT;
2528 bool writable = file->f_mode & FMODE_WRITE;
2529
2530 if (!psp_master || !psp_master->sev_data)
2531 return -ENODEV;
2532
2533 if (ioctl != SEV_ISSUE_CMD)
2534 return -EINVAL;
2535
2536 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
2537 return -EFAULT;
2538
2539 if (input.cmd > SEV_MAX)
2540 return -EINVAL;
2541
2542 mutex_lock(&sev_cmd_mutex);
2543
2544 switch (input.cmd) {
2545
2546 case SEV_FACTORY_RESET:
2547 ret = sev_ioctl_do_reset(&input, writable);
2548 break;
2549 case SEV_PLATFORM_STATUS:
2550 ret = sev_ioctl_do_platform_status(&input);
2551 break;
2552 case SEV_PEK_GEN:
2553 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
2554 break;
2555 case SEV_PDH_GEN:
2556 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
2557 break;
2558 case SEV_PEK_CSR:
2559 ret = sev_ioctl_do_pek_csr(&input, writable);
2560 break;
2561 case SEV_PEK_CERT_IMPORT:
2562 ret = sev_ioctl_do_pek_import(&input, writable);
2563 break;
2564 case SEV_PDH_CERT_EXPORT:
2565 ret = sev_ioctl_do_pdh_export(&input, writable);
2566 break;
2567 case SEV_GET_ID:
2568 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
2569 ret = sev_ioctl_do_get_id(&input);
2570 break;
2571 case SEV_GET_ID2:
2572 ret = sev_ioctl_do_get_id2(&input);
2573 break;
2574 case SNP_PLATFORM_STATUS:
2575 ret = sev_ioctl_do_snp_platform_status(&input);
2576 break;
2577 case SNP_COMMIT:
2578 ret = sev_ioctl_do_snp_commit(&input);
2579 break;
2580 case SNP_SET_CONFIG:
2581 ret = sev_ioctl_do_snp_set_config(&input, writable);
2582 break;
2583 case SNP_VLEK_LOAD:
2584 ret = sev_ioctl_do_snp_vlek_load(&input, writable);
2585 break;
2586 default:
2587 ret = -EINVAL;
2588 goto out;
2589 }
2590
2591 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
2592 ret = -EFAULT;
2593 out:
2594 mutex_unlock(&sev_cmd_mutex);
2595
2596 return ret;
2597 }
2598
2599 static const struct file_operations sev_fops = {
2600 .owner = THIS_MODULE,
2601 .unlocked_ioctl = sev_ioctl,
2602 };
2603
sev_platform_status(struct sev_user_data_status * data,int * error)2604 int sev_platform_status(struct sev_user_data_status *data, int *error)
2605 {
2606 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
2607 }
2608 EXPORT_SYMBOL_GPL(sev_platform_status);
2609
sev_guest_deactivate(struct sev_data_deactivate * data,int * error)2610 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
2611 {
2612 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
2613 }
2614 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
2615
sev_guest_activate(struct sev_data_activate * data,int * error)2616 int sev_guest_activate(struct sev_data_activate *data, int *error)
2617 {
2618 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
2619 }
2620 EXPORT_SYMBOL_GPL(sev_guest_activate);
2621
sev_guest_decommission(struct sev_data_decommission * data,int * error)2622 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
2623 {
2624 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
2625 }
2626 EXPORT_SYMBOL_GPL(sev_guest_decommission);
2627
sev_guest_df_flush(int * error)2628 int sev_guest_df_flush(int *error)
2629 {
2630 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
2631 }
2632 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
2633
sev_exit(struct kref * ref)2634 static void sev_exit(struct kref *ref)
2635 {
2636 misc_deregister(&misc_dev->misc);
2637 kfree(misc_dev);
2638 misc_dev = NULL;
2639 }
2640
sev_misc_init(struct sev_device * sev)2641 static int sev_misc_init(struct sev_device *sev)
2642 {
2643 struct device *dev = sev->dev;
2644 int ret;
2645
2646 /*
2647 * SEV feature support can be detected on multiple devices but the SEV
2648 * FW commands must be issued on the master. During probe, we do not
2649 * know the master hence we create /dev/sev on the first device probe.
2650 * sev_do_cmd() finds the right master device to which to issue the
2651 * command to the firmware.
2652 */
2653 if (!misc_dev) {
2654 struct miscdevice *misc;
2655
2656 misc_dev = kzalloc_obj(*misc_dev);
2657 if (!misc_dev)
2658 return -ENOMEM;
2659
2660 misc = &misc_dev->misc;
2661 misc->minor = MISC_DYNAMIC_MINOR;
2662 misc->name = DEVICE_NAME;
2663 misc->fops = &sev_fops;
2664
2665 ret = misc_register(misc);
2666 if (ret)
2667 return ret;
2668
2669 kref_init(&misc_dev->refcount);
2670 } else {
2671 kref_get(&misc_dev->refcount);
2672 }
2673
2674 init_waitqueue_head(&sev->int_queue);
2675 sev->misc = misc_dev;
2676 dev_dbg(dev, "registered SEV device\n");
2677
2678 return 0;
2679 }
2680
sev_dev_init(struct psp_device * psp)2681 int sev_dev_init(struct psp_device *psp)
2682 {
2683 struct device *dev = psp->dev;
2684 struct sev_device *sev;
2685 int ret = -ENOMEM;
2686
2687 if (!boot_cpu_has(X86_FEATURE_SEV)) {
2688 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
2689 return 0;
2690 }
2691
2692 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
2693 if (!sev)
2694 goto e_err;
2695
2696 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1);
2697 if (!sev->cmd_buf)
2698 goto e_sev;
2699
2700 sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE;
2701
2702 psp->sev_data = sev;
2703
2704 sev->dev = dev;
2705 sev->psp = psp;
2706
2707 sev->io_regs = psp->io_regs;
2708
2709 sev->vdata = (struct sev_vdata *)psp->vdata->sev;
2710 if (!sev->vdata) {
2711 ret = -ENODEV;
2712 dev_err(dev, "sev: missing driver data\n");
2713 goto e_buf;
2714 }
2715
2716 psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
2717
2718 ret = sev_misc_init(sev);
2719 if (ret)
2720 goto e_irq;
2721
2722 dev_notice(dev, "sev enabled\n");
2723
2724 return 0;
2725
2726 e_irq:
2727 psp_clear_sev_irq_handler(psp);
2728 e_buf:
2729 devm_free_pages(dev, (unsigned long)sev->cmd_buf);
2730 e_sev:
2731 devm_kfree(dev, sev);
2732 e_err:
2733 psp->sev_data = NULL;
2734
2735 dev_notice(dev, "sev initialization failed\n");
2736
2737 return ret;
2738 }
2739
__sev_firmware_shutdown(struct sev_device * sev,bool panic)2740 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic)
2741 {
2742 int error;
2743
2744 __sev_platform_shutdown_locked(&error);
2745
2746 if (sev_es_tmr) {
2747 /*
2748 * The TMR area was encrypted, flush it from the cache.
2749 *
2750 * If invoked during panic handling, local interrupts are
2751 * disabled and all CPUs are stopped, so wbinvd_on_all_cpus()
2752 * can't be used. In that case, wbinvd() is done on remote CPUs
2753 * via the NMI callback, and done for this CPU later during
2754 * SNP shutdown, so wbinvd_on_all_cpus() can be skipped.
2755 */
2756 if (!panic)
2757 wbinvd_on_all_cpus();
2758
2759 __snp_free_firmware_pages(virt_to_page(sev_es_tmr),
2760 get_order(sev_es_tmr_size),
2761 true);
2762 sev_es_tmr = NULL;
2763 }
2764
2765 if (sev_init_ex_buffer) {
2766 __snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer),
2767 get_order(NV_LENGTH),
2768 true);
2769 sev_init_ex_buffer = NULL;
2770 }
2771
2772 __sev_snp_shutdown_locked(&error, panic);
2773 }
2774
sev_firmware_shutdown(struct sev_device * sev)2775 static void sev_firmware_shutdown(struct sev_device *sev)
2776 {
2777 /*
2778 * Calling without sev_cmd_mutex held as TSM will likely try disconnecting
2779 * IDE and this ends up calling sev_do_cmd() which locks sev_cmd_mutex.
2780 */
2781 if (sev->tio_status)
2782 sev_tsm_uninit(sev);
2783
2784 mutex_lock(&sev_cmd_mutex);
2785
2786 __sev_firmware_shutdown(sev, false);
2787
2788 kfree(sev->tio_status);
2789 sev->tio_status = NULL;
2790
2791 mutex_unlock(&sev_cmd_mutex);
2792 }
2793
sev_platform_shutdown(void)2794 void sev_platform_shutdown(void)
2795 {
2796 if (!psp_master || !psp_master->sev_data)
2797 return;
2798
2799 sev_firmware_shutdown(psp_master->sev_data);
2800 }
2801 EXPORT_SYMBOL_GPL(sev_platform_shutdown);
2802
sev_get_snp_policy_bits(void)2803 u64 sev_get_snp_policy_bits(void)
2804 {
2805 struct psp_device *psp = psp_master;
2806 struct sev_device *sev;
2807 u64 policy_bits;
2808
2809 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
2810 return 0;
2811
2812 if (!psp || !psp->sev_data)
2813 return 0;
2814
2815 sev = psp->sev_data;
2816
2817 policy_bits = SNP_POLICY_MASK_BASE;
2818
2819 if (sev->snp_plat_status.feature_info) {
2820 if (sev->snp_feat_info_0.ecx & SNP_RAPL_DISABLE_SUPPORTED)
2821 policy_bits |= SNP_POLICY_MASK_RAPL_DIS;
2822
2823 if (sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED)
2824 policy_bits |= SNP_POLICY_MASK_CIPHERTEXT_HIDING_DRAM;
2825
2826 if (sev->snp_feat_info_0.ecx & SNP_AES_256_XTS_POLICY_SUPPORTED)
2827 policy_bits |= SNP_POLICY_MASK_MEM_AES_256_XTS;
2828
2829 if (sev->snp_feat_info_0.ecx & SNP_CXL_ALLOW_POLICY_SUPPORTED)
2830 policy_bits |= SNP_POLICY_MASK_CXL_ALLOW;
2831
2832 if (sev_version_greater_or_equal(1, 58))
2833 policy_bits |= SNP_POLICY_MASK_PAGE_SWAP_DISABLE;
2834 }
2835
2836 return policy_bits;
2837 }
2838 EXPORT_SYMBOL_GPL(sev_get_snp_policy_bits);
2839
sev_dev_destroy(struct psp_device * psp)2840 void sev_dev_destroy(struct psp_device *psp)
2841 {
2842 struct sev_device *sev = psp->sev_data;
2843
2844 if (!sev)
2845 return;
2846
2847 sev_firmware_shutdown(sev);
2848
2849 if (sev->misc)
2850 kref_put(&misc_dev->refcount, sev_exit);
2851
2852 psp_clear_sev_irq_handler(psp);
2853 }
2854
snp_shutdown_on_panic(struct notifier_block * nb,unsigned long reason,void * arg)2855 static int snp_shutdown_on_panic(struct notifier_block *nb,
2856 unsigned long reason, void *arg)
2857 {
2858 struct sev_device *sev = psp_master->sev_data;
2859
2860 /*
2861 * If sev_cmd_mutex is already acquired, then it's likely
2862 * another PSP command is in flight and issuing a shutdown
2863 * would fail in unexpected ways. Rather than create even
2864 * more confusion during a panic, just bail out here.
2865 */
2866 if (mutex_is_locked(&sev_cmd_mutex))
2867 return NOTIFY_DONE;
2868
2869 __sev_firmware_shutdown(sev, true);
2870
2871 return NOTIFY_DONE;
2872 }
2873
sev_issue_cmd_external_user(struct file * filep,unsigned int cmd,void * data,int * error)2874 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
2875 void *data, int *error)
2876 {
2877 if (!filep || filep->f_op != &sev_fops)
2878 return -EBADF;
2879
2880 return sev_do_cmd(cmd, data, error);
2881 }
2882 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
2883
sev_pci_init(void)2884 void sev_pci_init(void)
2885 {
2886 struct sev_device *sev = psp_master->sev_data;
2887 u8 api_major, api_minor, build;
2888
2889 if (!sev)
2890 return;
2891
2892 psp_timeout = psp_probe_timeout;
2893
2894 if (sev_get_api_version())
2895 goto err;
2896
2897 api_major = sev->api_major;
2898 api_minor = sev->api_minor;
2899 build = sev->build;
2900
2901 if (sev_update_firmware(sev->dev) == 0)
2902 sev_get_api_version();
2903
2904 if (api_major != sev->api_major || api_minor != sev->api_minor ||
2905 build != sev->build)
2906 dev_info(sev->dev, "SEV firmware updated from %d.%d.%d to %d.%d.%d\n",
2907 api_major, api_minor, build,
2908 sev->api_major, sev->api_minor, sev->build);
2909
2910 return;
2911
2912 err:
2913 sev_dev_destroy(psp_master);
2914
2915 psp_master->sev_data = NULL;
2916 }
2917
sev_pci_exit(void)2918 void sev_pci_exit(void)
2919 {
2920 struct sev_device *sev = psp_master->sev_data;
2921
2922 if (!sev)
2923 return;
2924
2925 sev_firmware_shutdown(sev);
2926 }
2927